Problema Solution
William has 20 coins. All are nickels and dimes. The combined value is $1.60. How many nickels does he have?
Answer provided by our tutors
Let X to be total numbers of Nickels and Y to be total numbers of Dimes
Equation 1:
X + Y = 20
X = 20-Y
Equation 2: Substitute X=20-Y
(0.05X + 0.10Y) = 1.60 (Both sides x100)
5X + 10Y = 160
5(20-Y) + 10Y = 160
100 - 5Y + 10Y = 160
5Y = 60
Y = 12
Substitute Y = 12 into Equation 1
X = 20-Y
= 20 - 12
= 8