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Andrew and Carol had 160 dollars altogether. Andrew gave 1/3 of his money to Carol. Then carol gave 1/5 of the amount
she had back to Andrew. Finally both had 80 dollars each. How much did Andrew have at first.
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1. Let x = "How much did andrew have at first".
Then Carol had (160-x) dollars.
2. When Andrew gave 1/3 of his money to Carol, Carol had = dollars.
3. Then Carol gave 1/5 of the amount she had back to Andrew. After that Carol had dollars.
And the condition says that this amount is exactly 80 dollars:
= 80.
It is your equation to find "x". First, multiply both sides by . You will get
160 - (2/3)x}}} = = 100. ====>
= 160 - 100 = 60 ====> x = = 90.
Answer. Andrew had 90 dollars at first. // which means that Carol had 160-90 = 70 dollars at first.
Check. After n.2 exchange Andrew had 90-30 = 60; Carol had 70+30 = 100 dollars.
After n.3 exchange Andrew had 60+20 = 80; Carol had 100-20 = 80.
80 = 80. ! Correct !
Solved.