A jar of dimes and quarters contains $15.25. There are 103 coins in the jar all together. How much of each are there?
can someone tell me the answer, the equation used to find the answer and how to do it thx..
2007-05-22 14:34:38 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
10D + 25 Q = 1525
D + Q = 103
D = 103 - Q, substitute into line 1
10(103 - Q) + 25 Q = 1525
1030 - 10Q + 25 Q = 1525
15 Q = 495
Q = 33
D = 103 - 33 = 70
2007-05-22 14:38:57 · answer #1 · answered by richardwptljc 6 · 0⤊ 0⤋
Let x= number dimes
then y = number of quarters
x + y = 103
0.10x + 0.25y = 15.25
Let's use substitution, you could use other methods.
x = 103 - y
Substitute into value equation
0.10(103 - y) + 0.25 y = 15.25
simplify
10.3 - 0.10y + 0.25 y = 15.25
0.15y = 4.95
y = 33 number of quarters
103 - 33 = 70 number of dimes
Let's prove
0.25*33 + 0.10*70 = 15.25
15.25 = 15.25
.
2007-05-22 14:55:36 · answer #2 · answered by Robert L 7 · 0⤊ 0⤋
x= 10 cents coins
y= 25 cents coins
x+y=103
10x + 25y= 1525 cents
solving equations, multiply the first eq. by -10
then you eliminate x, 15 y = 1525-1030=495
y=495/15= 33 quarters
x= 70 dimes
2007-05-22 14:47:26 · answer #3 · answered by mimi 3 · 0⤊ 0⤋
.1d + .25q = 15.25
d + q = 103 or d = 103 - q
.1(103 - q) + .25q = 15.25
10.3 - .1q + .25q = 15.25
10.3 - .1q +.25q = 15.25
.15q = 4.95
q = 33
d + q = 103
d + 33 = 103
d = 70
Quarters = 33
Dimes = 70
2007-05-22 14:44:13 · answer #4 · answered by Juissez 1 · 0⤊ 0⤋
0.1d+0.25Q=15.25
d+q=103
theres your eqations, but i forgot how to solve the rest, because we did this stuff a long time ago.. sorry :(
2007-05-22 14:43:44 · answer #5 · answered by mikki<3 2 · 0⤊ 0⤋