Number problems. Jill has $3.50 in nickels and dimes. If she has 50 coins, how
many of each type of coin does she have?
2007-05-31 16:06:04 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
We take cents as calculation is always easier when one deals with whole numbers.
Jill has 350 cents
Let the no. of nickels be x and the no. of dimes be y
x + y = 50 ........ (1)
5x + 10y = 350
x + 2y = 70 ....... (2)
(2) - (1),
x + 2y - (x + y) = 70 - 50
y = 20
Put y = 20 in (1)
x + 20 = 50
x = 30
Jill has 30 nickels and 20 dimes
2007-05-31 16:13:55 · answer #1 · answered by Akilesh - Internet Undertaker 7 · 0⤊ 0⤋
20 dimes and 30 nickels
2007-05-31 23:12:13 · answer #2 · answered by pczdemon 1 · 0⤊ 0⤋
30 nickles and 20 dimes 30 nickels= $1.50+20 dimes=$2.00 $1,50 +$2.00=$3.50 20 + 30 = 50
2007-05-31 23:18:10 · answer #3 · answered by yp_tim_gillett 2 · 0⤊ 0⤋
x + y =50
.05x+.10y=3.50 or 5x+10y=350
y=50-x
5x+10(50-x)=350
5x+500-10x=350
-5x=350-500=-150
5x=150
x=30
therefore y=50-30=20
you have 30 nickels and 20 dimes
Follow my work to make sure you understand. Try and learn from it.
2007-05-31 23:16:27 · answer #4 · answered by John M 2 · 0⤊ 0⤋
20 dimes, 30 nickels
5x+10y=350
x+y=50
x=50-y
250-5y+10y=350
5y=100
y=20 dimes
x=30 nickels
2007-05-31 23:13:22 · answer #5 · answered by hello! 2 · 1⤊ 0⤋
You have 2 expressions/formulas that you can write-
nickles + dimes = 50
nickles x 0.05 + dimes x 0.10 = 3.50
If you multiply the 2nd equation by 10 you get-
nickles x 0.5 + dimes = 35.00
subtract the resulting equation from the first equation-
nickles + dimes = 50
0.5 nickles + dimes = 35
------------------------------------
0.5 nickles = 15
so you have 30 nickles + 20 dimes
2007-05-31 23:22:15 · answer #6 · answered by skipper 7 · 0⤊ 0⤋
n+d=50
0.05n+0.10d=3.5...multiply by 20x:
n+2d=70...subtract 1st equation from this:
d=20
n=30
2007-05-31 23:10:02 · answer #7 · answered by gebobs 6 · 1⤊ 0⤋