Question

Ten percent of the reds are added to twenty percent of the blues, and the total is 24. Yet the product of the number of reds and 3 exceeds the number of Blues by 20. How many are red and how many are blue?

Answer 1

0.10r + 0.20b = 24
3r = b + 20....b = 3r - 20

0.10r + 0.20(3r - 20) = 24
0.10r + 0.60r - 4 = 24
0.70r = 24 + 4
0.70r = 28
r = 28/0.70
r = 40 <=== there are 40 reds

0.10r + 0.20b = 24
0.10(40) + 0.20b = 24
4 + 0.20b = 24
0.20b = 24 - 4
0.20b = 20
b = 20/0.20
b = 100 <=== there are 100 blues