Question

Rita bought some large packets of salt weighing 500grams each and some small packets of salt weighing 200 grams each. If she has 8 packets altogether and they weigh 2200 grams in total, how many of each kind does she have?

Answer 1

L+S=8, L=8-S

500L+200S=2200, using L from above in this equation gives you:

500(8-S)+200S=2200

4000-500S+200S=2200

4000-300S=2200

-300S=-1800

S=6, and since L=8-S:

L=2

So Rita bought 2 large packets and 6 small packets.