Suppose you have $9.60 in dimes and quarters. How many of each coin would you have if you have twice as many quarters as dimes?
Please don't just give me 16 dimes and 32 quarters I know that is the answer I just can't figure out how to get there
2007-03-29 05:41:08 · 10 answers · asked by calired67 4 in Science & Mathematics ➔ Mathematics
All those were great answers thanks well except that one but hey. It isn't easy being 39 and going back to school.
2007-03-29 06:02:38 · update #1
x = number of dimes
2x = number of quarters
.25(2x) + .1(x) = 9.6
.5x + .1x = 9.6
5x + 1x = 96
6x = 96
x = 16
number of dimes = 16
number of quarters = 32
2007-03-29 05:45:30 · answer #1 · answered by Anonymous · 3⤊ 0⤋
Hey there, no worries! This is a pretty fun question to solve.
You can use x to denote the number dimes because the amount you need is still unknown.
As the question states you have twice as many quarters as you do dimes, and the amount is also unknown, use 2x.
A dime is worth 10 cents or .10 dollars, whilst a quarter is worth 25 cents or .25 dollars. (We changed the value to the dollar form as $9.60 is given in the dollar form. You can choose to keep the values in the cents form, but then you will need to convert $9.60 into 960 cents. It doesn't really matter which you do, the more important thing is which ever is easier for you.)
Therefore, to find the amount of coins you need, use the mathematical sentence --
x (.10) [this refers to the dimes] + 2x (.25) [this refers to the quarters] = 9.60
.10x + .50x = 9.60
.60x = 9.60
x = 9.60 / .60
x = 16
Amount of dimes needed
= x
= 16
Amount of quarters needed
= 2x
= 2 x 16
= 32
Hope this helped! :)
2007-03-29 12:55:45 · answer #2 · answered by shopaholicstace 2 · 1⤊ 0⤋
You have 960 cents
( 25 x q) + (10 x d) = 960.......q is the no of quarters and d is the no of dimes
25q + 10d = 960
q = 2d
50d + 10d = 960
60d = 960
d = 16
There are 16 dimes and 2 times 16 quarters , 32 quarters
2007-03-29 13:16:41 · answer #3 · answered by rosie recipe 7 · 0⤊ 0⤋
Lets say that 10d + 25q = 960
and q = 2d
Then sub the second equation into the first to get
10d + 50d = 960
60d = 960
=> d = 16
and q = 2d => q = 2 * 16 = 32
2007-03-29 12:48:48 · answer #4 · answered by biglildan 6 · 1⤊ 0⤋
Let x be the number of dimes.
You know that you have twice as many quarters as dimes.
Hence, the number of quarters is 2x.
You know the total value is $9.60.
That's 0.10 times the number of dimes, plus 0.25 times the number of quarters.
Hence, 0.10*x + 0.25*(2x) = 9.60
Simplifying: 0.6x = 9.60
6x = 96
x = 16
so you have 16 dimes.
Since you have twice as many quarters as dimes, you have 32 quarters.
Hope that helps!
2007-03-29 12:49:53 · answer #5 · answered by Bramblyspam 7 · 1⤊ 1⤋
D dimes + Q quarters = 9.60
Q = 2D (twice as many)
D dimes + 2D quarters = 9.6
D * .10 + 2D *.25 = 9.6 (a dime is .10, a quarter is .25)
Solve for D and you get dimes, multiply by 2 and you get quarters.
2007-03-29 12:49:30 · answer #6 · answered by Vegan 7 · 1⤊ 0⤋
Let q = number of quarters and d = number of dimes
From the question you know that
q = 2*d and .25*q + .10*d = 9.60
Substitute in for q
.25(2*d) + .10d = 9.60
.5d + .1d = 9.6
.6d = 9.6
d = 9.6/.6
d = 16 so q = 32
2007-03-29 12:47:40 · answer #7 · answered by Jeffrey O 3 · 1⤊ 0⤋
x = number of dimes
2x = number of quarters
So.1x+.25(2x) = 9.6
.1x+.5x=9.6
.6x= 9.6
x = 9.6/.6= 16 = number of dimes
2x =2*16=32 = number of quarters
2007-03-29 12:50:58 · answer #8 · answered by ironduke8159 7 · 1⤊ 0⤋
System of equations:
25Q + 10D = $9.60
Q = 2D
Solve by substitution:
25(2D) + 10D = 9.60
60D = 9.60
Etc.
2007-03-29 12:47:30 · answer #9 · answered by tedfischer17 3 · 1⤊ 0⤋
It's pretty much a matter of hit and miss. Try it with a couple #'s and if they dont work, adjust them accordingly
2007-03-29 12:46:43 · answer #10 · answered by brookesinger 2 · 0⤊ 4⤋