Question 957318
I have to make $1.00 using 30 coins, pennies,nickels, dimes, quarters...How can I do this
:
It's pretty hard, you got 4 unknowns and only two equation. Let $1 be 100 cents
1p + 5n + 10d + 25q = 100
p  +  n +  d +  q = 30
------------------------Subtraction eliminates p
0 + 4n + 9d + 24q = 70
The numbers of quarters has to be 1 or 2, assume we have 1 quarter
4n + 9d = 70 - 24
4n + 9d = 46
4n = -9d + 46
n = {{{(-9d+46)/4}}}
the only value for d that will give an integer value for is d=2
n = {{{(-9(2)+46)/4}}}
n = {{{28/4}}}
n = 7 nickels
Now we have 7 nickels, 2 dimes and 1 quarter
p + 7 + 2 + 1 = 30
p = 30 -10
p = 20 pennies
:
See if that works
.01(20) + .05(7) + .10(2) + .25(1) = 1.00
.20 + .35 + .20 + .25 = 1.00