Asked by Anonymous
A coin bank contains some twenty-cent and fifty-cent coins in the ratio of 4 : 5. When 16 fifty-cent coins were taken out and replaced by some twenty-cent coins, the ratio became 8 : 7. The total value of the twenty-cent coins added was the same as the total value of the fifty-cent coins taken out. Find the sum of money in the coin box
Answers
Answered by
mathhelper
original number of 20 c's --- 4x
original number of 50 c's ---- 5x
new number of 50 c's = 5x - 16
we took out 16 half-dollars , or we took out $8
these were replaced by 20 cent pieces equal to that value, that is,
we added 40 twenty cents coins , and now have 4x + 40
new ratio of 25 c's : 50 c's = 8 : 7
(4x + 40) / (5x - 16) = 8/7
40x - 128 = 28x + 280
12x = 408
x = 34
original amount:
number of 20 c coins = 4(34) = 136
number of 50 c coins = 5(34) = 170
value = 20(136) + 50(170) = ........
original number of 50 c's ---- 5x
new number of 50 c's = 5x - 16
we took out 16 half-dollars , or we took out $8
these were replaced by 20 cent pieces equal to that value, that is,
we added 40 twenty cents coins , and now have 4x + 40
new ratio of 25 c's : 50 c's = 8 : 7
(4x + 40) / (5x - 16) = 8/7
40x - 128 = 28x + 280
12x = 408
x = 34
original amount:
number of 20 c coins = 4(34) = 136
number of 50 c coins = 5(34) = 170
value = 20(136) + 50(170) = ........
There are no AI answers yet. The ability to request AI answers is coming soon!
Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.