Question

Sally is $3.95 in dimes and quarters that shows the total 23 coins how many times does she have and how many quarters does she have

Answer 1

Make a system of equations:

0.10x + 0.25y = 3.95
x + y = 23

x + y = 23

Subtract 'y' to both sides:

x = -y + 23

Plug in -y + 23 for 'x' in the first equation:

0.10(-y + 23) + 0.25y = 3.95

Distribute 0.10:

-0.10y + 2.3 + 0.25y = 3.95

Subtract 2.3 to both sides:

-0.10y + 0.25y = 1.65

Combine like terms:

0.15y = 1.65

Divide 0.15 to both sides:

y = 11

Plug this into any of the two equations to find 'x':

x + y = 23

x + 11 = 23

Subtract 11 to both sides:

x = 12

So Sally has 11 dimes and 12 quarters.