SOLUTION: A purse contains $3.75 in 5-cent and 20-cent coins. If there are 33 coins altogether, how many of each type of coin do I have?
Algebra.Com
Question 723727: A purse contains $3.75 in 5-cent and 20-cent coins. If there are 33 coins altogether, how many of each type of coin do I have?
Found 2 solutions by josmiceli, mananth:
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = number of 5 cent coins
Let = number of 20 cent coins
--------------
given:
(1)
(2) ( in cents )
----------------------
Multiply both sides of (1) by
and subtract (1) from (2)
(2)
(1)
and, since
(1)
(1)
(1)
19 = number of 5 cent coins
14 = number of 20 cent coins
check answer:
(2)
(2)
(2)
(2)
OK
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
1 x + 1 y = 33 .............1
Total value
5 x + 20 y = 375 .............2
Eliminate y
multiply (1)by -20
Multiply (2) by 1
-20 x -20 y = -660
5 x + 20 y = 375
Add the two equations
-15 x = -285
/ -15
x = 19
plug value of x in (1)
1 x + 1 y = 33
19 + y = 33
y = 33 -19
y = 14
y = 14
x= 19 number of 5 cent coins
y= 14 number of 20 cent coins
RELATED QUESTIONS
Michelle has $12.30 in her purse in 1 cent, 5 cent, 10 cent and 25 cent coins. If she... (answered by Alan3354)
I need to know how to set up this equation. Please explain the logic behind how you set... (answered by nerdybill)
Elaine has 88 coins in a purse which are all 5-cent coins and 10-cent coins. The total... (answered by ikleyn,Theo)
I have a purse with several coins in it. The coins have values of 1 cent, 5 cents, 10... (answered by ankor@dixie-net.com)
A coin purse contains 5 cents, 10 cents and 25 cents coins. The number of 10 cents-coins... (answered by ikleyn)
Colin has a jar containing only 5-cent and 20-cent coins. In total, there are 31 coins... (answered by josgarithmetic,MathTherapy)
In my purse I have 21 coins, all of which are either 5-cent or 20-cent coins. Their total (answered by ikleyn)
A money box contains only 20 cent coins and 50 cent coins. If there are 57 coins in the... (answered by stanbon)
A money box contains only 10-cent
and 20-cent coins. There are 34
coins with a total... (answered by ikleyn)