David was fixing a jigsaw puzzle. On the second day, the number of pieces he fixed was 50% of the total number of pieces. After another two weeks, he fixed another 156 pieces and was left with 10% of the jigsaw puzzle unfixed. How many pieces were left unfixed?
|
Fixed |
Unfixed |
Total |
Before
|
1 x 5 = 5 u |
1 x 5 = 5 u |
2 x 5 = 10 u |
Change |
+ 156 |
- 156 |
|
After |
9 u |
1 u |
10 x 1 = 10 u |
50% =
50100 =
12 Fixed : Total = 1 : 2
10% =
10100 =
110 Unfixed : Total = 1 : 10
Number of more pieces that David fixed
= 9 u - 5 u
= 4 u
4 u = 156
1 u = 156 ÷ 4 = 39
Number of pieces left unfixed
= 1 u
= 1 x 39
= 39
Answer: 39