28 Aretha has 0.85 in nickels and dimes.She has 2 more nickels than dimes.How many nickels and dimes does she have?
2007-01-14 09:35:25 · 4 answers · asked by Wii 1 in Science & Mathematics ➔ Mathematics
Let d = amount of dimes Aretha has. Also, it is given she has 2 more nickels than dimes, so she has (d + 2) nickels.
Since nickels are represented as 0.05, and x of them would mean x(0.05), or (0.05)x, this is exactly how we write "d + 2" of them.
We have d dimes and d + 2 nickels, which is supposed to add up to 0.85, so
(0.10)d + (0.05)[d + 2] = 0.85
Decimals are annoying. I choose to multiplying both sides by 100, to eliminate them.
10d + 5(d + 2) = 85
Expand the left hand side,
10d + 5d + 10 = 85
Now, simplify.
15d + 10 = 85
15d = 75
d = 5
So we know that we have 5 dimes. Given that we have two more nickels than dimes, it follows we have 7 nickels.
2007-01-14 09:41:55 · answer #1 · answered by Puggy 7 · 1⤊ 0⤋
if x = number of dimes, x + 2 must be the number of nickels
(x * 10) + ((x + 2) * 5) = 85
(15 * x) + 10 = 85
15 * x = 75
x = 5
Aretha has 5 dimes and 7 nickels
2007-01-14 17:53:41 · answer #2 · answered by michaell 6 · 0⤊ 0⤋
5
2007-01-14 17:43:10 · answer #3 · answered by your boss 2 · 0⤊ 0⤋
x*10+(x+2)*5=85
15x+10=85
15x=75
x=5
she has 5 nickels and 7 dimes
2007-01-14 17:39:52 · answer #4 · answered by raj 7 · 0⤊ 0⤋