Question

1. Mark and Bill have a combined weight of 170

Answer 1

Equation : x + y = 170 and y = 2x - 40

The weight of Bill is 70 pounds and weight of mark is 100 pounds

Solution:

Let the weight of Bill be "x"

Let the weight of mark be "y"

Given that,

Mark and Bill have a combined weight of 170  pounds

Therefore,

x + y = 170 ------- eqn 1

Mark weighs 40 pounds less than twice Bill's  weight

y = 2x - 40 ------- eqn 2

Substitute eqn 2 in eqn 1

x + 2x - 40 = 170

3x = 170 + 40

3x = 210

x = 70

Substitute x = 70 in eqn 2

y = 2(70) - 40

y = 140 - 40

y = 100

Thus weight of Bill is 70 pounds and weight of mark is 100 pounds