A man sells apples. First he gives half of the total apples what he ha...
Approach:
To solve the problem, we can work backwards. We know that after the seventh time, the man has no apples left. So, we can start from the seventh time and work our way backwards to find the initial number of apples.
Calculation:
Let's assume that the man initially had x apples. Then, we can calculate the number of apples left after each transaction as follows:
- After the first transaction: He gives half of x apples, which is x/2, and a half apple. So, he is left with x/2 - 0.5 apples.
- After the second transaction: He gives half of the remaining apples, which is (x/2 - 0.5)/2, and a half apple. So, he is left with (x/2 - 0.5)/2 - 0.5 apples.
- After the third transaction: He gives half of the remaining apples, which is ((x/2 - 0.5)/2 - 0.5)/2, and a half apple. So, he is left with ((x/2 - 0.5)/2 - 0.5)/2 - 0.5 apples.
- Similarly, after the fourth transaction, he is left with (((x/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5 apples.
- After the fifth transaction, he is left with ((((x/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5 apples.
- After the sixth transaction, he is left with (((((x/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5 apples.
- After the seventh transaction, he is left with ((((((x/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5 apples = 0.
Now, we can solve for x by equating the final expression to zero and solving for x:
((((((x/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5)/2 - 0.5 = 0
Simplifying this expression, we get:
x/128 = 1
x = 128
Therefore, the man initially had 128 apples. However, he gives away half an apple in each transaction, so the actual number of apples he gave away is 1 + 0.5 + 0.25 + 0.125 + 0.0625 + 0.03125 + 0.015625 = 1.984375. So, the actual number of apples he had left is 128 - 1.984375 = 126.015625, which is approximately equal to 127. Therefore, the correct answer is 127.