Tammy had a collection of 1790 brown, purple and silver marbles. After Tammy gave away 210 brown marbles, the number of brown marbles was 240 fewer than the number of purple marbles. Given that the number of silver marbles was five times as many as the number of purple marbles, how many brown marbles did Tammy have at first?
| |
Brown marbles |
Purple marbles |
Silver marbles |
Total |
| Before |
1 u + 210 |
1 u + 240 |
5 u + 1200 |
1790 |
| Change |
- 210 |
|
|
|
| After |
1 u |
1 u + 240 |
5 u + 1200 |
|
Number of silver marbles in the end
= 5 x (1 u + 240)
= 5 u + 1200
Total number of marbles at first
= 1 u + 210 + 1 u + 240 + 5 u + 1200
= 7 u + 1650
7 u + 1650 = 1790
7 u = 1790 - 1650
7 u = 140
1 u = 140 ÷ 7 = 20
Number of brown marbles that Tammy had at first
= 1 u + 210
= 20 + 210
= 230
Answer(s): 230
