the average age of a class of 20 students is 15 years and the average age of another class of 30 students is 20 years .find the average age of students into classes​

Answers

Answer 1

Let’s say the first class is X.

Avg(X)= x/20=15

X=300

Let’s say the second class is Y.

Avg(Y)= Y/30=20

Y=600

X+Y=900

AVG(X+Y)=900/(20+30)=900/50=18

The average of both classes is 18.


Related Questions

If a distribution for a quantitative variable is thought to be nearly symmetric with very little variation,and a box and whisker plot is created for this distribution,which of the following is true?
A) The box will be quite wide but the whisker will be very short.
B) The left and right-hand edges of the box will be approximately equal distance from the median.
C) The whiskers should be about half as long as the box is wide.
D) The upper whisker will be much longer than the lower whisker.

Answers

Answer:

B). The left and right-hand edges of the box will be approximately equal distances from the median.

Step-by-step explanation:

The 'symmetry' si described as a 'satisfying arrangement of a balanced distribution of the elements of the whole' while a 'symmetry group' is characterized as a group whose elements are all the transformations under which a given object remains invariant and whose group operation is function composition.

As per the given conditions, the second statement asserts a true claim regarding the keeping of edges of left, as well as, right-hand side's boxes at equal intervals from the median. This will help in making the arrangement fulfilling while keeping a little scope for the variation. Thus, option B is the correct answer.

how much does a customer save for buying a sound system marked $1,200 at a discount of 15%​

Answers

Answer:

Step-by-step explanation:

Mp=$1200

Let sp be x

SP=MP-discount% of MP

x=1200-15/100 * 1200

x=120000-18000/100

x=102000/100

x=1020

the amount of money person saves=MP-SP

=$1200-$1020

=$180

therefore he saves $180

What is the slope between the two points (2,8) ;(3,12)

Answers

Answer:

4

Step-by-step explanation:

If we have two points we can  find the slope

m = ( y2-y1)/(x2-x1)

   = (12-8)/(3-2)

    = 4/1

   = 4

what is the answer to this question

Answers

Answer: Your Answer to this question is C. Can you mark me as Brainliest and a thanks plss!!

4. It was 68.7°F at midday, then it rose 9°F in the afternoon and dropped another 12.3°F by 7:00 p.m. What was the temperature at 7:00p.m.?​

Answers

The temperature rose so you add the amount it rose to the starting temperature

68.7 + 9 = 77.7 degrees

It then dropped so mow you subtract t the amount it dropped:

77.7 - 12.3 = 65.4 degrees

The answer is 65.4 degrees

the mean of the numbers 5, 2x, 4 and 3 is 5 find the value of x

Answers

Answer:

X=4

Step-by-step explanation:

(5+4+3+2x)/4=5

(12+2x)/4=5

12+2x=20

2x=8

X=4

How do you do an explicit formula for a geometric problem

Answers

Answer:

State the initial term.

Find the common ratio by dividing any term by the preceding term.

Substitute the common ratio into the recursive formula for a geometric sequence.

Express the percent as a decimal.
41%

Answers

Answer:

0.41

Step-by-step explanation:

41/100

0.41

hope it helps

Answer:

0.41

Step-by-step explanation:

Percentages, fractions, and decimals are tightly connected.

When breaking the meaning of "percent" down, you get "per" (for each) and "cent" ("hundred" in French), so a percent is always a number over 100.A fraction is one number divided by another, a part of a whole.A decimal is a number expressed with the base-ten system of counting.

This being said, if you get 41%, remember that you can write it as a fraction of the number over 100, which would be [tex]\frac{41}{100}[/tex]. You can then turn it into a decimal*, which would be 0.41.

*when you have a two-digit whole number as the numerator of a fraction with denominator 100, the decimal form would just be 0. the numerator and the percent would be the numerator %. If the numerator is a whole one-digit number and the denominator is 100, the decimal form would be 0.0 the numerator, and the percent would still be just the numerator %.

e.g. for a fraction of [tex]\frac{17}{100}[/tex], the decimal is 0.17 and the percent is 17%.e.g. for a fraction of [tex]\frac{3}{100}[/tex], the decimal is 0.03 and the percent is 3%.

The table below shows Michaels' income and expenditure for the month of
April 2021. Study the table and answer the questions that follow.
Income
Amount
Andont
R15 435.20
Funeral Plan
Salary
Expenses (Variable)
R 200
R2050
Rent
Petrol
Air Time
Food (Groceries)
Clothing
R 500
R 350
R 400
R 700
School Fees
Car Repayment
Car Insurance
Total Expenditures
R600
R4 500
R 317
A
Entertainment
R 900
R 300
Toiletries
B
Money Left Over
1.1.1 Determine the values of A and B.
Use the value of B to decide whether the family is using the money wisely (2)​

Answers

Huh? This makes no sense could you maybe write it in your own words

Convert to scientific notation: 0.000112

Answers

Answer:

Answer is=112power -4

please make me brainlest pls

Answer:

[tex]10^{-4}[/tex]x 1.12

Step-by-step explanation:

4 times to the right

{2x + y = -1}
{3x- 5y + -21}

Answers

Answer:

(-2, 3).

Step-by-step explanation:

2x + y = -1

3x- 5y = -21

Multiply the first equation by 5:

10x + 5y = -5     Adding this to the second equation:

13x = -26

x = -2.

Substituting this into equation 1:

2(-2) + y = -1

y = -1 + 4 = 3.

Checking this result in the second equation:

3(-2) - 5(3)

= -5 - 15 = -21

- Checks OK.

23
1 Which of the following numbers makes
the inequality below true?
2.5p < 14
Ap=5
Bp=6
cp=7
Dp = 8
lo What is the value of n in the countion

Answers

Answer:

A. p=5

Step-by-step explanation:

2.5x5=12.5

The rest are over 14

Hope this helps! :)

When a coin is tossed it is either heads or tails. Suppose heads has a point value of 1 and tails a point value of -1. if the sum of the point value after 50 tosses is 14. How many of the tosses must have been heads?

Answers

Answer:

32

Step-by-step explanation:

Totally there are 50 tosses.  

Let the number of tosses which resulted head be x.  

Therefore the number of tosses which resulted tail is 50−x.

We get x×1+(50−x)×(−1)=14

x−(50−x)=14

x−50+x=14

x=32

In 1993, the moose population in a park was measured to be 4100. By 1998, the population was measured again to be 3000. If the population continues to change linearly

Answers

there seems to be missing text

Due today.. I'm Stuck and need help please). The table shows the test scores and the sleep averages of several students. A) Write the least squares regression equation that models the data. Let x = the test score and y = average sleep. B) Use the equation to determine the approximate test score of a student who sleeps an average of 8 hours a night. Show Your Work. ( Will Mark Brainliest but no Links or nonsense answers please). Answer A and Answer B.​

Answers

Answer:

Y = -0.3587+0.09118X

92 %

Step-by-step explanation:

Using technology to fit the data between the variables, test score and hours of sleep; we obtain the linear model :

Ŷ = -0.3587+0.09118X

Where, x = test score ; y = hours of sleep

To obtain the test score of a student who sleep foe 8 hours using the model :

Y = 8

Ŷ = -0.3587+0.09118X

8 = -0.3587+0.09118X

8 + 0.3587 =0.09118X

8.3587 = 0.09118X

X = 8.3587 / 0.09118

X = 91.672515

X = 92 ( approximately)

One of the legs of a right triangle measures 16 cm and the other leg measures 8 cm. Find the measure of the hypotenuse. If necessary, round to the nearest tenth.

Answers

Answer:

17.9

Step-by-step explanation:

Use the Pythagorean theorem, c²= a² + b². We can rewrite it as c = √(a² + b²),  a=16 and b=8. Plug it in as c = √(16² + 8²) then simplify.

c = √(16² + 8²)

c = √(256 + 64)

c = √320

c≈17.9 (rounded to the nearest tenth)

what type of triangle measuring 60cm, 100 cm, 40 cm

Answers

Answer:

Not a triangle

Step-by-step explanation:

Not a triangle.

The sum of the lengths of any two sides of a triangle has to be greater than the length of the third side.

40 + 60 is not greater than 100

therefor it is not a triangle

1. After you retire in 17 years your goal is to have $100,000 in your investment account that earns 8% compounded annually. How much money would you need to deposit now to reach this goal

Answers

9514 1404 393

Answer:

 $27,026.90

Step-by-step explanation:

The future value formula can be solved to find the present value required.

  FV = P(1 +r)^t . . . future value of P compounded at annual rate r for t years

  $100,000 = P(1 +0.08)^17

  P = $100,000/3.70002 . . . . divide by the coefficient of P

  P = $27,026.90

You would need to deposit #27,026.90 now to reach this goal.

Choose 3 values that would make this inequality true. n - 3 ≤ 10
14
15
5
10
22
13
30

Answers

Answer:

5, 10 and 13

Step-by-step explanation:

5 - 3 = 2 < 10

10 - 3 = 7 < 10

13 - 3 = 10 = 10

Suppose 56% of recent college graduates plan on pursuing a graduate degree. Twelve recent college graduates are randomly selected.
a. What is the probability that no more than three of the college graduates plan to pursue a graduate degree? (Round your final answer to 4 decimal places.)
b. What is the probability that exactly eight of the college graduates plan to pursue a graduate degree? (Round your final answer to 4 decimal places.)
c. What is the probability that at least six but no more than ten of the college graduates plan to pursue a graduate degree? (Round your final answer to 4 decimal places.)

Answers

A____________________

Identify factors that influence the significance level and power of a hypothesis test. Which of the following statements is FALSE?

a. Alpha (a) is equal to the probability of making a Type I error.
b. A smaller sample size would increase the effectiveness of a hypothesis test.
c. The probability of rejecting the null hypothesis when the null hypothesis is true is called a Type 1 Error.
d. The power of a hypothesis test is the probability of not making a Type Il error.

Answers

Answer:

b. A smaller sample size would increase the effectiveness of a hypothesis test.

Step-by-step explanation:

A hypothesis test is an important procedure in the field of statistics. It evaluates any two mutually exclusive statements about a population that determines and tells which statement made best supports to the sample data provided.

Now we know that an increase in the sample size makes the hypothesis test more effective and sensitive and it is more likely to reject the null hypothesis.

The probability of making a type I error is known as the Alpha while the probability of making type II error is called Beta.

Thus the correct option is (b).

Answer:

A smaller sample size would increase the effectiveness of a hypothesis test

Step-by-step explanation:

Megan worked 20 hours last week. This
week she worked 80% more hours. How
many more hours did she work this week 2

Answers

Answer:

16 more hours for a total of 36 hours.

Step-by-step explanation:

C= 20 × .8

C= 16

T= 20 + C

T = 20 + 16

T = 36

Two buses leave towns 520 kilometers apart at the same time and travel toward each other. One bus travels 16 km/h slower than the other. If they meet in 2 hours, what is the rate of each bus?

Answers

Answer:

122 km/h

138 km/h

Step-by-step explanation:

distance = speed * time

One bus travels 16 km/h slower than the other

(s * 2)  + (s - 16)2 = 520

2s + 2s - 32 = 520

4s = 552

s = 552/4

s = 138 km/h

s - 16 = 122 km/h

Click on the measure of the gangle.

Answers

Answer:

34

Step-by-step explanation:

The bottom line is at 180

The top line is at 146

180-146 =34

I believe the answer is 34

Find the value of x . PLEASE ANSWER QUICK ILL MARK BRAINLIEST

Answers

Answer:

x = 30°

Step-by-step explanation:

(3x) = 90

[tex](3x)/3=90/3[/tex]

   x     [tex]=[/tex]   30

Hence, x = 30°

URGENT HELP! SOLVE FOR A
answer choices : 24.6
27.8
18.7
44.2

Answers

9514 1404 393

Answer:

  (b)  27.8

Step-by-step explanation:

The relevant trig relation is ...

  Cos = Adjacent/Hypotenuse

  cos(22°) = a/30

  a = 30×cos(22°) ≈ 27.8

salma is 1.45 meters tall. at 3p.m she measures the length of a tree's shadow to 29.35 meters. she stands 24.3 meters away from the tree, so that the tip of her shadow meets the tip of the treels shadow. find the height of the tree to the nearest hundreth of a meter.

Answers

Answer:

23.67

Step-by-step explanation:

Answer:

kimjnuhbygvtcfrdxe

Step-by-step explanation:

Select Yes or No to state whether each data set is likely to be normally distributed

Answers

Answer:

No

Step-by-step explanation:

no more animals in zoo

no average of animals at San Diego zoo is high

no visitors are more than 2k

Answer:

Step-by-step explanation:

average age of an elephant at a zoo- YES

number of elephants at the San Diego Zoo- NO

number of daily visitors at the San Diego Zoo- YES

took the test :)

HELPPPPPPPPPPPPPPPP!!!!!!

Answers

Answer:

70.2 degrees

Step-by-step explanation:

[tex]\arccos \left(\frac{19}{56}\right)=1.22463\ = \quad \begin{pmatrix}\mathrm{Degrees:}&70.17^{\circ \:}\end{pmatrix}[/tex]

What is the result when the number 84 is decreased by 50%?

Answers

Answer:

42

Step-by-step explanation:

Answer:

42

84 ×50%by100 =42. 84-42= 42. hope helpful answer
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