Answer:
The 1st and 4th statements are true.
Is it multiple choice or do you have to write a answer?
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 inches
Step-by-step explanation:
The area of a triangle = bh/2
where b = base = unknown
h = height = 5 3/4 inches
Area = 46 inches²
Therefore, 46 = base × 5 3/4 / 2
Cross multiply
46 × 2 = base × 5 3/4
92 = base × 5 3/4
Base = 92 ÷ 5 3/4
Base = 92 ÷ 23/4
Base = 92 × 4/23
Base = 4 × 4
Base = 16 inches