Question

Lilly has a bag of 140 colored marbles. The bag has an equal number of green and blue marbles and an equal number of red and yellow marbles. If Lilly arranged all of the green marbles in groups of 8 and all of the blue marbles in groups of 7, how many red marbles are in the bag?

A) 8
B) 14
C) 22
D) 28

PLEASE HELP!!!!

Answer 1

The answer will be C. 22

Answer 2

LCM of 8 and 7 = 56

then,

56 x 2 = 112 (green and blue)

140 - 112 = 28 (red and yellow)

28 ÷ 2 = 14 red