Question

a coin purse contain a mixture of 32 coins in dimes and quarters. The coins have a total value of $5 or 500 cents. Determime. the number of dimes and the number of quarters in the purse.

Answer 1

Let the number of dimes be x
Let the number of quarters be y

x+y=32
10x + 25y = 500

Solve for x and y

x = 20
y= 12

Check,
20+12 = 32

20(10) + 12(25) = 500

Hence Proved.

Answer 2

n + q = 32
n.05 + q.25 = 5

q = (5-32(.05))/(.25-.05) = 17

17(.25) + 15(.05) = 5.00

Answer 3

why did i read nickels instead of dimes?

Answer 4

Its 25c and 10c

Answer 5

yeah, i see that now lol

Answer 6

q = (5-32(.10))/(.25-.10) = 12

and the rest is yada yada ....

Answer 7

thanks for both of your help.

Answer 8

youre welcome, now if you ever need to know the one about the nickels ... lol

Answer 9

I'm little lost with this equation q = (5-32(.10))/(.25-.10) = 12

Answer 10

Keep it in cents, that way you don't have to deal with too many decimal points.

Answer 11

its an application of cramers rule to determine the amount of quarters

Answer 12

once we got the equations:

d + q = 32
d.10 + q.25 = 5

we can eliminate the ds or qs; lets get rid of the ds by multiplying by -.10


d(-.10) + q(-.10) = 32(-.10)
d.10 + q.25 = 5
----------------------------
q(.25-.10) = 5-32(.10) ; and solve for q

q= (5-32(.10))/(.25-.10)