Question

The sum of two numbers is 70. the first number is 2/5 of the second number. What are the numbers?

Answer 1

A + b = 70
a = 2/5b

2/5b + b = 70
2/5b + 5/5b = 70
7/5b = 70
b = 70 * 5/7
b = 350/7
b = 50

a = 2/5b
a = 2/5(50)
a = 100/5
a = 20

the numbers are 50 and 20....the smallest being 20 and the largest being 50

Answer 2

X + 2/5x = 70
1x + 2/5x = 70
1 2/5 x = 70
7/5 x = 70  multiply both sides by 5
7x = 350  divide both sides by 7
x = 50    so 2/5 x = 20    the two numbers are 50 and 20
the larger of the two is 50