cindy has three times as many dimes as pennies and one less nickel than the number of pennies. if she has a total of $2.47, how many of each type of coin does she have?
2006-09-12 08:44:16 · 7 answers · asked by ddd d 1 in Science & Mathematics ➔ Mathematics
any more homeworks?!
well, if p=no.of pennies, d=no.of dimes, n=no.of nickels, then
d = 3p (three times as many dimes as pennies)
n = p-1 (one less nickel than the number of pennies)
operate in pennies now:
dime value = 30 p
nickel value = 5(p-1)
total = 30p+5p-5+p = 247 or 36p = 252 or p=7
hence 7 pennies, 21 dimes, 6 nickels
2006-09-12 08:54:58 · answer #1 · answered by m s 3 · 0⤊ 1⤋
she has:
21 dimes
7 pennies
6 nickels
EXPLAINATION:
substitute x for the number of pennies she has.
she has 3 times the number of pennies for dimes, so:
3(.10)x + x
(note: .10 equal how much a dime is worth)
and then...she has one less the number of pennies for dimes, so:
3(.10)x + x + .5(x-1)
and the total of that is $2.47, so...
3(.10)x + x+ 5(x-1) = $2.47
30x + x + 5x - 5 = $2.47
.36x = $2.52
x = 7
since x = the number of pennies she had...you can substitute in x for the equations for dimes and nickels:
number of dimes = 3x
number of dimes = 21
number of nickels = x-1
number of nickels = 6
$2.10 + $0.30 + $0.07 = $2.47
2006-09-12 15:58:17 · answer #2 · answered by meeeesh 3 · 0⤊ 1⤋
your gonna have 21 dimes which is 2.10 plus 6 nickels which is .30 plus 7 pennies which is 7 cents and that adds up to 2.47
2006-09-12 16:01:34 · answer #3 · answered by kevin n 1 · 0⤊ 1⤋
d = 3p
n = p - 1
.01p + .05n + .10d = 2.47
p + 5n + 10d = 247
p + 5(p - 1) + 10(3p) = 247
p + 5p - 5 + 30p = 247
36p - 5 = 247
36p = 252
p = 7
d = 3(7) = 21
n = 7 - 1 = 6
ANS :
7 pennies
6 nickles
21 dimes
2006-09-12 16:35:43 · answer #4 · answered by Sherman81 6 · 0⤊ 1⤋
u know, i really dont mind if u need some help,but ur basically asing us to do ur hw 4 u, bc u hv asked dif q's about math in order. u shud do ur own hw.
2006-09-12 15:53:27 · answer #5 · answered by lexa (: 4 · 1⤊ 0⤋
3(#P)*0.10 + (#P-1)*0.05 + (#P) = 2.47
2006-09-12 15:52:45 · answer #6 · answered by Holden 5 · 0⤊ 1⤋
do your own homework, lazy kid!
2006-09-12 15:50:08 · answer #7 · answered by forjj 5 · 1⤊ 0⤋