Answer:
The sum rule is f' + g'
The difference rule is f' − g'
The product rule is f g' + f' g
The quotient rule is (f' g − g' f )/g2
Given:
3 kids
72 is the product of their ages.
There is a youngest child.
This means that all three are of different ages. We need to factor 72 into 3 integers.
Let us use prime factorization:
72 ÷ 2 = 36
36 ÷ 2 = 18
18 ÷ 2 = 9
9 ÷ 3 = 3
Prime factors are: 2 x 2 x 2 x 3 x 3 OR 2³ x 3²
3 ages.
eldest = 3³ = 9
middle = 2² = 4
youngest = 2¹ = 2
2 x 4 = 8
8 x 9 = 72
X + 4x = 75
Combine like terms:
5x = 75
Divide by 5 on each side of the equal sign:
x = 15
