Question: Sarah buys 20 pencils on Monday. Then she buys 18 more pencils on Tuesday. On Wednesday she buys triple the number of pencils she did on Tuesday. How many pencils does she have?
Solution:
By adding together Monday and Tuesday, Saah has 20+18= 38 pencils
On Wednesday, she buys 3 * 18= 54 pencils
All together, Sarah has 38+54= 92 pencils
Answer: 92