Billy had to paint some boxes. On the first day, the number of boxes he painted was 30% of the number of boxes that he had not painted. One week later, he painted another 690 boxes. As a result, the total number of painted boxes became 24 more than
45 of the total number of boxes. How many less boxes were painted than unpainted on the first day?
|
Painted |
Not painted |
Total |
Before
|
3x5 = 15 u |
10x5 = 50 u |
13x5 = 65 u |
Change |
+ 690 |
- 690 |
|
After |
15 u + 690 |
50 u - 690 |
65 u |
Comparing painted and not painted boxes in the end |
4x13 + 24 = 52 u + 24 |
1x13 - 24 = 13 u - 24 |
5x13 = 65 u |
30% =
30100 =
310Painted : Not painted = 3 : 10
The total number of boxes remains unchanged. Make the total number of boxes at first and in the end the same. LCM of 13 and 5 is 65.
The number of boxes painted in the end is repeated.
52 u + 24 = 15 u + 690
52 u - 15 u = 690 - 24
37 u = 666
1 u = 666 ÷ 37 = 18
Number of less boxes that were painted than not painted on the first day
= 50 u - 15 u
= 35 u
= 35 x 18
= 630
Answer(s): 630