Question

Liz had 140 pens and Inna had 100 pens. After Inna gave Liz some pens, Liz had 3 times as many pens as Inna. How many pens did Inna give Liz?

Answer 1

Answer:

140 + x = 3 * (100 - x)

140 + x = 300 - 3x

140 + 4x = 300

4x = 160

x = 40

Inna gave Liz 40 pens.