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:
y=1, x=1
Step-by-step explanation:
This is a 90-45-45 triangle. One side is a sq root 2, and the other sides are a and a.
For example, if one side was 3 sq root two, then the other sides would be 3 and 3
Answer:
shegot a better score on the second test
50 is double of 25
75is 3 times 25
100 is 4 times 25
Step-by-step explanation:
19 times 4= 76
17 times 5= 85