Answer:
314 m²
Step-by-step explanation:
the formula for the surface area of a sphere (As) is
As = 4×pi×r²
the radius r (half of the diameter) is clearly indicated as 5m.
so, As = 4×3.14×5² = 4×3.14×25
I don't even need a calculator for this, as 4×25 = 100
so, As = 100×3.14 = 314
(you know, when multiplying by 10, the decimal point moves right one position. multiply by 100 it moves 2 positions, and so on).
Answer: 1 = y
All you have to do is carry the 2 over and subtract it from 6 so then you just have 4=4y which will turn into 1=y
The ration of boy campers to total campers is 8:15, and the ratio of girl campers to total campers is 7:15. Using this information, we can answer this question by setting up proportions.
<u>For boys:</u>

<em>*Cross multiply*</em>
15x=1560
<em>*Divide both sides by 15*</em>
x=104
There are 169 boy campers.
<u>For girls:</u>

<em>*Cross multiply*</em>
15x=1365
91=x
There are 91 girl campers.
Hope this helps!!
Answer:
C. 
Step-by-step explanation:
Given the two equations:

To find:
The correct option when value of y is substituted to 2nd equation using the 1st equation.
Solution:
First of all, let us learn about the substitution method.
Substitution method is the method to provide solutions to two variables when we have two equations and two variables.
In substitution method, we find the value of one variable in terms of the other variable and put this value in the other equation.
Now, the other equation becomes only single variable and then we solve for the variable's value.
Here, we have two equations and value of one varible is:

Let us put value of y in 2nd equation:

So, the correct answer is option C. 