show all steps using system of equations
2007-01-31 14:33:33 · 10 answers · asked by Amy B 1 in Science & Mathematics ➔ Mathematics
Let D = number of dimes, Q = number of quarters.
So
(.10)D + (.25)Q = 15.25
D + Q = 103
D = 103 - Q
Substitute this into the first equation
(.10)(103-Q) + (.25)Q = 15.25
then solve for Q
Q = 33
Then solve for D
D = 70
2007-01-31 14:39:47 · answer #1 · answered by yaachan3 3 · 2⤊ 0⤋
Assuming there are x no of dimes and y no of quarters altogether.
Eqn 1; 10 x + 25 y = 1525
Eqn 2 ; x + y = 103
Eq 2 x 10; 10 x + 10y = 1030 ; Eqn 3
Eqn 1 - Eqn 3; 15y = 495
therefore, y = 33
From Eqn 2; x = 103 -33 = 70.
Answer: 70 dimes & 33 qtr in the jar.
QED
2007-01-31 14:46:12 · answer #2 · answered by kanlim 3 · 0⤊ 0⤋
$ 15.25 = 1525 cents
Quarter = 25 cents
Dime = 10 cents
Number of dimes = x
Number of quarters = 103 - x
10x + 25(103 - x) = 1525
Solve for x
x = 70 dimes
103 - x = 103 - 70 = 33 quarters
2007-01-31 14:47:36 · answer #3 · answered by Sheen 4 · 0⤊ 0⤋
D+Q=103
D=103-Q
(1/10)D+(1/4)Q=15.25
(1/10)(103-Q)+(1/4)Q=15.25
(206/20)-(2Q/20)+(5/20)Q=15.25
(206/20)+(3/20)Q=305/20
206+3Q=305
3Q=99
Q=33
D+Q=103
D+33=103
D=(103-33)=70
(1/10)70+(1/4)33
7+8.25=15.25
70 Dimes and 33 Quarters
2007-01-31 15:01:57 · answer #4 · answered by Michelle M 2 · 0⤊ 0⤋
let d = dimes
let q = quarters
I usually switch everything to cents so I don't misplace my decimal points. (I've seen to many people convert a nickel to .5).
d + q = 103 (because that's how many coins there are)
10d + 25q = 1525(because that's how much they're worth)
At this point, I would solve by elimination. If you multiply the top equation by negative ten you can eliminate d.
-10d - 10q = -1030
10d + 25q = 1525
Add both columns
15q = 495
Divide both sides by 15.
q = 33
If there are 33 quarter then there should be 70 dimes.
Common sense check. .25(33) + .10(70) = 8.25 + 7 = 15.25
2007-01-31 14:42:31 · answer #5 · answered by mirramai 3 · 0⤊ 0⤋
33 quarters and 70 dimes
2007-01-31 14:40:27 · answer #6 · answered by xx x 1 · 0⤊ 0⤋
OK here you go.
let number of dimes = d
let number of quarters = q
0.10d +0.25q = 15.25
d +q = 103
two equations two unknows. solve one equation for one of the unkowns in terms of the other. Subsitute it into the other equation and solve. You do the crunching.
2007-01-31 14:41:25 · answer #7 · answered by Roadkill 6 · 0⤊ 0⤋
The answer is "C". Trust me I'm a mathematician.
2007-01-31 14:37:38 · answer #8 · answered by Anonymous · 0⤊ 0⤋
DO your own homework
2007-01-31 14:36:11 · answer #9 · answered by Anonymous · 0⤊ 0⤋
This is a homework question isn't it?
2007-01-31 14:35:46 · answer #10 · answered by jaycie685 2 · 0⤊ 0⤋