Number Sense Blog

By Mathnasium | Added Jul 4, 2018

What project would you like to accomplish over the summer? Whatever it is, you might need math to make it happen. It this week’s word problem challenge Tej needs to figure out how long it will take him to finish a brick wall he’s building. Practice your elementary and middle school math skills as you figure out the challenge.

Take your time and think it through. When you're ready, check below for the solution!

Question: Tej is building a brick wall. The entire wall will have 486 bricks. On the first day, he lays 243 bricks but was more and more tired as the days went on. Each day after the first he only lays 2/3 of the number of bricks left from the previous day. How many days did it take Tej to finish the wall?

Solution: First we find 486 − 243 = 243 bricks left to lay after the first day. Each of the following days he lays 2/3 the amount he did the previous day. 2/3 of 243 = 162. He laid 162 bricks on day 2, leaving 243 − 162 = 81 bricks to be laid. If we repeat this process, at the end of day 6 he will only have 1 more brick to lay. Since we can’t take a fraction, day 7 will be an easy one and Tej will only have to lay one brick.

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