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  Number and Math Play

Building Blocks
 
Q Jeannine is bored playing with blocks while babysitting her baby brother. To keep herself amused, she decides to stack up all the blocks so that each row has one less block than the row below. There are a total of 55 blocks, and Jeannine wants to end up with just 1 block on top. How many should she put in the bottom row?
 
 
A The bottom row will have 10 blocks.

Start at the top and work backwards, listing rows and the total number of blocks used

Row/Blocks   Total Blocks
1   1
2   3
3   6
4   10
5   15
6   21
7   28
8   36
9   45
10   55

STRATEGY: MAKE A TABLE AND WORK BACKWARDS