math
posted by jorge .
Anita and Maria went to the candy store. Maria bought 5 pieces of fudge and 3 pieces of bubble gum for a total of $5.70. Anita bought 2 pieces of fudge and 10 pieces of bubble gum for a total of $3.60. Determine the cost of 1 piece of bubble gum.

5f + 3b = 5.7
2f + 10b = 3.6
Multiply first equation by 2 and second by 5 to make 10f in both equations. Subtract one equation from another and solve for b.