Mary had a total of 285 green and white balls. She used
35 of her green balls and bought another 66 white balls. The number of white balls she had then become
15 the number of green balls. How many less white balls than green balls did she have at first?
| |
Green balls |
White balls |
| Before |
5x5 |
|
| Change |
- 3x5 |
+ 66 |
| After |
2x5 |
|
| Comparing balls in the end |
5x2 |
1x2 |
| |
Green balls |
White balls |
| Before |
25 u |
2 u - 66 |
| Change |
- 15 u |
+ 66 |
| After |
10 u |
2 u |
The number of green balls in the end is repeated.
LCM of 2 and 5 is 10.
Total number of green balls and white balls
= 25 u + 2 u - 66
= 27 u - 66
27 u - 66 = 285
27 u = 285 + 66
27 u = 351
1 u = 351 ÷ 27 = 13
Number of less white balls than green balls at first
= 25 u - (2 u - 66)
= 23 u + 66
= 23 x 13 + 66
= 365
Answer(s): 365
