Answer:
10
Step-by-step explanation:
Let c = sum of ages of all children.
mean age of all children = c/15 = 7
c = 15 * 7 = 105
The sum of the ages of all children is 105.
Let b = sum of ages of the 9 boys.
mean age of boys = b/9 = 5
b = 9 * 5 = 45
The sum of the ages of the boys is 45.
The sum of the ages of the girls is c - b.
c - b = 105 - 45 = 60
The number of girls is 15 - 9 = 6
mean age of girls = (sum of ages of the girls)/(number of girls) =
= 60/6 = 10
Answer:
Step-by-step explanation: You have to do the distributive property to get the answer.
The value of the number is 80,000
Answer:
20
Step-by-step explanation:
8/2=4
The workers were split in half, so the hours would go up:
10*2=20
I hope you understand what I mean...
:)
Answer:
<em>Sam is 30 years old, and Harry is 10 years old.</em>
Step-by-step explanation:
Let us assume that the age of Sam is x and the age of Harry is y.
Sam is currently is three times Harry's age.
So, 
----------------------1
Sam's age is also 10 more than twice Harry's age.
so, 
---------------2
Subtracting 2 from 1, we get
putting this in equation 1,
Therefore, Sam is 30 years old, and Harry is 10 years old.
