Question 10785
Let x = number of nickels, since it is the last part at the end of the first phrase.
3x = number of dimes
x+2 = number of quarters


Total value of the coins = value of each coin times the number of coins.  You can work in dollars or cents.  I recommend that you use cents, so change $2.90 to 290 cents.


5(x) + 10(3x) + 25(x+2) = 290 cents
5x + 30x + 25x + 50 = 290
60x + 50 = 290
60x + 50-50 = 290-50
60x = 240
x= 4  Nickels
3x = 12 Dimes
x+2 = 6 Quarters


Check: Find the values of all the coins.
x= 4  Nickels  = $.20
3x = 12 Dimes    1.20
x+2 = 6 Quarters 1.50


Total value = $2.90  
It checks.


R^2 at SCC


See my Lesson Plans on Word Problems for Basic Algebra!!!