Question

Darlene bought some 30 cent and some 60 cent candy bars. Altogether she bought 10 candy bars and paid a total of $4.20. How many candy bars at each price did she buy?

Answer 1

.3x+.6y = 4.2
x+y = 10
x = 10-y
3-.3y+.6y=4.2
.3y = 1.20
y = 4 candy bars

x = 10-y
x = 10 - 4 = 6 candy bars