Question 1160512
b = black
c = colored
b+c = 24
0.15b+0.21c = 4.02
Use substitution
b = 24-c
0.15(24-c)+0.21c = 4.02
3.6-0.15c+0.21c = 4.02
3.6+0.06c = 4.02
0.06c = 4.02-3.6
0.06c = 0.42
Divide both sides by 0.06
c = 7
b = 24-7
b = 17
Check----
0.15b+0.21c = 4.02