Question

A bag contains blue marbles and red marbles, 56 in total. The number of blue marbles is 8 more than 2 times the number of red marbles. How many blue marbles are there?

Answer 1

24 Blue marbles.

Explanation:

56 - 8 = 48

48 / 2 = 24

so if there are 24 blue marbles, 24 x 2 = 48, and then 8 more is 56.

Answer 2

40

Explanation:

b + r = 56 (1)

b = 2r + 8 (2)

(1) r = 56 - b

(2) b = 2(56 - b) + 8

b = 112 - 2b + 8

3b = 120

b = 120÷3

b = 40