SOLUTION: Find the cost of 7 pens if 3 cost 45p.

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Find the cost of 7 pens if 3 cost 45p.      Log On


   

Question 901327: Find the cost of 7 pens if 3 cost 45p.
Found 2 solutions by ewatrrr, Jc0110:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
3%2F45+=+7%2Fx | Cross Multiplying to solve
3x = 315
x = 105p

Answer by Jc0110(165) About Me  (Show Source):
You can put this solution on YOUR website!
Step 1: Find the cost for 1 pen.
CostForOnePen=45%2F3=15
Therefore, cost for 1 pen is 15p.

Step 2: Find the cost for 7 pens.
CostForFivePens=15%2A7=105
Therefore, cost for 7 pens is 105p.