Exaplin and illustrate

Question

Otis has 12 coins in his pocket worth $1.10. If he only has nickels, dimes and quarters, what are all of the p combinations?"

Answer 1

N+D+Q =12

.05N+.10D+.25Q = $1.10

3rd restriction is each has to be an integer

one Quarter, 6 Dimes, + 5 Nickels = 12 coins

5(.05) +6(.10) +1(.25) = .25+.60+ ,25 = $1.10

or zero Quarters, 10 dimes, 2 Nickels = 12 coins

.10(10) + .05(2) = 1.00 +.10 = $1.10