A, B, C and D each had some money. D doubled the amounts with the others. C then doubled the amounts with others. B then doubled the amounts with the others. A then doubled the amounts with the others. At this stage, each of them has $80. Find the initial amount with C.
Help me!!
each person had $1.25
Because:
There are four of them, therefore $1.25*4=5
They then each double the previous amount, so: 5*2*2*2*2=$80
or in reverse:80/2/2/2/2=5
5/4+1.25
To solve this problem, we'll work backwards. Let's start with the final stage, where each person has $80.
At stage 4 (initial amount doubled by A):
- A has $80.
- Based on the information given, B would have had $40 before the doubling by A.
- Now that A doubled B's amount, B's initial amount would have been $40 / 2 = $20.
At stage 3 (initial amount doubled by B):
- B has $80.
- Based on the information given, C would have had $20 before the doubling by B.
- Now that B doubled C's amount, C's initial amount would have been $20 / 2 = $10.
At stage 2 (initial amount doubled by C):
- C has $80.
- Based on the information given, D would have had $10 before the doubling by C.
- Now that C doubled D's amount, D's initial amount would have been $10 / 2 = $5.
Finally, at stage 1 (initial amount doubled by D):
- D has $80.
- Based on the information given, each person initially had the same amount, which we'll call X.
- Now that D doubled X, we have the equation: X * 2 = $5.
- Solving for X, we divide both sides by 2: X = $5 / 2 = $2.50.
Therefore, the initial amount with C was $10.