Thursday
May 5, 2016

Posted by Tiffany on Tuesday, October 18, 2011 at 4:14pm.

Sally has three times as many dimes as nickels and twice as many quarters as dimes.In all she has \$5.55. How many coins of each type does she have?
Let 2x=quarters
3x=dimes

3 nickels .15
9 dimes .90
18 quarters 4.50
total 5.50

It's easy enough to check.

You added wrong at the very end. 4.50 + .90 + .15 does indeed make 5.55

However, your equations do not represent the facts:

x = nickels
3x = dimes
2(3x) = 6x = quarters

5x + 10(3x) + 25(6x) = 555
185x = 555
x=3

Megan has three times as many quarters than nickels. She has one less dime than the number of quarters. If she has a total of \$4.30, how many of each coin does she have ?

Nickels = x
Quarters = 3x
Dimes = 3x-1

Plug in equation with coin values in ()...
(5)x + (25)3x + (10)3x-1 = 430
5x + 75x + 30x - 10 = 430
80x + 30x - 10 = 430
110x -10 = 430
110x -10 +10 = 430 + 10
110x = 440
x = 4
Nickels = 4 (x)
Quarters = 12 (3x)
Dimes = 11 (3x-1)

4x5=20 N
12x25=300 Q
11x10=110 D /
/
20+300+110= 430 cents \/