Ron bought 8 pencils and 2 erasers for $1.66. Sarah bought 12 pencils and 5 erasers for $3.19. What is the cost for 1 pencil and 1 eraser?

P=price of 1 pencil

e=price of 1 eraser

1.66=8p+2e

divide by 2 for simplification

0.83=4p+e

3.19=12p+5e

0.83=4p+e

multiply by - 5 and add to obht eration

-4.15=-20p-5e

3.19=12p+5e +

-0.96=-8p

divide by - 8

0.12=p

sub back

0.83=4p+e

0.83=4 (0.12) + e

0.83=0.48+e

minus 0.48 both sides

0.35=e

1e+1p=0.12+0.35=0.47

cosst is $0.47