SOLUTION: paul has twice as many dimes as pennies and 3 times as many nickels as pennies. in all he has 1.80? how many coins of each type does he have?

Algebra ->  Customizable Word Problem Solvers  -> Coins -> SOLUTION: paul has twice as many dimes as pennies and 3 times as many nickels as pennies. in all he has 1.80? how many coins of each type does he have?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 508726: paul has twice as many dimes as pennies and 3 times as many nickels as pennies. in all he has 1.80? how many coins of each type does he have?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +p+ = number of pennies
Let +n+ = number of nickels
Let +d+ = number of dimes
given:
(1) +d+=+2p+
(2) +n+=+3p+
(3) +1%2Ap+%2B+5n+%2B+10d+=+180+ ( in pennies )
Substitute (1) and (2) into (3)
(3) +p+%2B+5%2A3p+%2B+10%2A2p+=+180+
(3) +p+%2B+15p+%2B+20p+=+180+
(3) +36p+=+180+
(3) +p+=+5+
and
(1) +d+=+2p+
(1) +d+=+10+
and
(2) +n+=+3p+
(2) +n+=+15+
There are 5 pennies, 15 nickels, and 10 dimes
check answer:
(3) +1%2Ap+%2B+5n+%2B+10d+=+180+
(3) +5+%2B+5%2A15+%2B+10%2A10+=+180+
(3) +5+%2B+75+%2B+100+=+180+
(3) +180+=+180+