12. The owner of a store displays a large jar of nickels and dimes and offers the value of the coins to the person who guesses how many dimes there are. If there are 1,130 coins, and they are worth $100, how many dimes are there?

Question

anonymous · Answer

5N + 10D = 100
N + D = 1130

anonymous · Answer

Can you solve from there?

anonymous · Answer

no can you tell me more details please

anonymous · Answer

Ok I see the problem sorry it should be:

0.05N + 0.10D = 100
N + D = 1130

anonymous · Answer

So, multiply eq.1 by -20 and add to eq.2

0.05N + 0.10D = 100
               -2D   = -870

D = 435 coins.
which makes N = 695 coins.

anonymous · Answer

i got it thank you