Ask question

Ask question

All categories

3 years ago

9

In Mrs. Robinson's class, there are 16 girls and 14 boys. The mean of the girls' heights is 63.7 inches, and the mean of the boy

s' heights is 65.4 inches. What is the mean of the heights of all 30 students? Express your answer as a decimal to the near tenth.

1 answer:

Elodia [21]3 years ago

8 0

Answer: 64.6

Step-by-step explanation:

If you add up 63.7 and 65.4 and then divide by 2 you get 64.6.

You might be interested in

HELP ME SOLVE HURRY I WILL MARK BRAINLIEST THANKS

adelina 88 [10]

Answer:

your y intercept is 90 and the equation would be y= 90 and x is unknown

5 0

3 years ago

Myra is a scientist and needs 45 gallons of a 16% acid solution. The lab is currently stocked only with a 20% acid solution and

asambeis [7]

Answer:

The volume of the solution with 20% acid is 27 gallons and the one with 10% acid is 18 gallons

Step-by-step explanation:

Myra needs to mix "x" gallons of the solution with 20% and "y" gallons of the solution with 10%. The volume of the final solution must be 45 gallons, therefore:

x + y = 45

The concentration of acid of the final solution is:

0.2*x + 0.1*y = 45*0.16

0.2*x + 0.1*y = 7.2

Therefore we have a system of equation:

x + y = 45

0.2*x + 0.1*y = 7.2

We need to multiply the first equation by -0.1:

-0.1*x -0.1*y = -4.5

0.2*x + 0.1*y = 7.2

We now sum both equation:

0.1*x = 2.7

x = 2.7/0.1 = 27 gallons

y = 45 - 27 = 18 gallons

6 0

4 years ago

natalie guessed on the last four true or false questions on her math quiz. what is the probability that she got all four quiz qu

Verizon [17]

Each question is either true or false, so the sample space is 2, true and false, two states only.

what's the probability she got one correct, well, the favorable outcomes is 1, possible outcomes is 2, so 1/2.

what's the probability that she got all four correct, we simply multiply the probability of each,

$\bf \cfrac{1}{2}\cdot \cfrac{1}{2}\cdot \cfrac{1}{2}\cdot \cfrac{1}{2}\implies \cfrac{1}{16}\implies 0.0625\qquad or\qquad 6.25\%$

7 0

3 years ago

Juanita and Keenan own a camping supply store and just put in an order for flashlights and sleeping bags. The number of flashlig

julsineya [31]

Juanita and Keenan ordered 85 flashlights and 17 sleeping bags.

Step-by-step explanation:

Given,

Cost of each flashlight = $12

Cost of each sleeping bag = $45

Total cost = $1785

Let,

x represent the number of flashlights ordered

y represent the number of sleeping bags ordered

According to given statement;

12x+45y=1785 Eqn 1

x = 5y Eqn 2

Putting value of x from Eqn 2 in Eqn 1

$12(5y)+45y=1785\\60y+45y=1785\\105y=1785\\$

Dividing both sides by 105

$\frac{105y}{105}=\frac{1785}{105}\\y=17$

Putting y=17 in Eqn 1

$x=5(17)\\x=85$

Juanita and Keenan ordered 85 flashlights and 17 sleeping bags.

Keywords: linear equation, substitution method

Learn more about substitution method at:

#LearnwithBrainly

8 0

4 years ago

Agata [3.3K]

Answer:

1. x = 0, 4, -9

2. x = 3, 3, -5

3. 2x^3 - 9x^2 + 7x + 6

4. x = -6, -8, -15

5. 2x^3+10x^2+12x

Factor out the common factor:

2x (x^2+5x+6 )

Factor what's left in parentheses:

2x (x + 2) (x + 3)

6. x = 0, 4, -9

Step-by-step explanation:

5 0

3 years ago