SOLUTION: mr.magoo's piggy bank contains 46 dimes and quarters. The value of his coins is $6.70. how many of each type of coin does he have?

Algebra.Com
Question 551946: mr.magoo's piggy bank contains 46 dimes and quarters. The value of his coins is $6.70. how many of each type of coin does he have?
Answer by TutorDelphia(193)   (Show Source): You can put this solution on YOUR website!
So we know two basic facts:
d+q=46 (the number of dimes plus the number of quarters in 46)
And the values add up to 6.70
d*.10+q*.25=6.70
Now its easy to see this is a systems of equations problem. You can solve it with substitution or elimination.
I'll use elimination.
d+q=46
d*.10+q*.25=6.70 (divide both sides by .1 (which happens to be the same as multiplying by 10))
d+q*2.5=67
d+q=46 subtract this equation from the other one
q*1.5=21
q=14
sub in for q
d+14=46
d=32
If you did it by substitution you'd have to solve the equation:
(46-q)*.10+q*.25=6.70



RELATED QUESTIONS

A child’s piggy bank contains 35 coins and a total of $6.25. The bank contains... (answered by ikleyn)
A child's piggy bank contains nickels, dimes, and quarters. There are twice as many... (answered by jorel1380)
A piggy bank contains 20 coins, consisting of nickel and dimes. How many of each type of (answered by ankor@dixie-net.com)
mark has 42 coins consisting of dimes and quarters. the total value of his coins is $6.... (answered by lynnlo)
Mike has 19 coins (nickels, dimes, and quarters) in his piggy bank with a total value of... (answered by nyc_function,Fombitz)
Emily has nickels, dimes, and quarters in her piggy bank. She has twice as many dimes as... (answered by ankor@dixie-net.com)
Emily has nickels, dimes, and quarters in her piggy bank. She has twice as many dimes as (answered by Fombitz)
Zachary has nickels, dimes and quarters in his piggy bank. He has 58 coins with a total... (answered by lwsshak3)
A piggy bank contains 30 coins worth $1.90. (A) If the bank contains only nickels and... (answered by josgarithmetic,greenestamps)