There are 64 blue and red marbles in a box. The ratio of red marbles and blue marbles is 3:5. How many blue marbles are there?

Question

Plz Help me I'm stuck on this question!!!

Answer 1

total marbles=64
ratio of red and blue marbles=3:5
let the red marbles=3a
then,the blue marbles=5a
so,
3a+5a=64
8a=64
a=64/8
a=8
then the blue marbles=5×8
=40

Answer 2

Thx Anaji