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:
16 tricycles
12 bicycles
Step-by-step explanation:
If all were bicycles, there would be 28·2 = 56 wheels. Each additional wheel indicates the presence of a tricycle instead of a bicycle.
There are 72 -56 = 16 tricycles. The remaining 28-16 = 12 are bicycles.
Assuming the pay last month was from Jayla's new job, it represents pay for weekly hours of ...

Jayla worked an average of 37 hours each week.