1. **State the problem:** Five people went to a restaurant. Four of them each spent $12 less than the average amount spent by all five together, and the fifth person spent $18 less than twice the average. We need to find the total amount spent by the fifth person.
2. **Define variables:** Let the average amount spent by all five people be $x$.
3. **Express amounts spent:**
- Each of the four people spent $x - 12$.
- The fifth person spent $2x - 18$.
4. **Write the equation for the total amount spent:**
$$4(x - 12) + (2x - 18) = 5x$$
5. **Simplify the equation:**
$$4x - 48 + 2x - 18 = 5x$$
$$6x - 66 = 5x$$
6. **Solve for $x$:**
$$6x - 5x = 66$$
$$x = 66$$
7. **Find the amount spent by the fifth person:**
$$2x - 18 = 2(66) - 18 = 132 - 18 = 114$$
8. **Check the options:** None of the options list 114 for the fifth person, so let's verify the problem statement carefully.
**Re-examining the problem:** It says "Four of them spent $12 less than the average amount of money they spent together" and "the fifth person spent $18 less than twice the average." The average is for all five people.
Let's check the total sum with $x=66$:
- Four people: $4 imes (66 - 12) = 4 imes 54 = 216$
- Fifth person: $114$
- Total: $216 + 114 = 330$
Average: $330 / 5 = 66$, which matches $x$.
9. **Compare with options:** The options show repeated amounts for the first four people and a different amount for the fifth. Let's check which option matches the pattern:
- Option 1: $56, 56, 56, 56, 58$ total $56*4 + 58 = 282$ average $282/5=56.4$ no
- Option 2: $48, 48, 48, 48, 88$ total $48*4 + 88 = 280$ average $56$ no
- Option 3: $52, 52, 52, 52, 72$ total $52*4 + 72 = 280$ average $56$ no
- Option 4: $44, 44, 44, 44, 104$ total $44*4 + 104 = 280$ average $56$ no
None match the average 66 we found.
10. **Check if the problem meant the average of the four people, not all five:**
Let $y$ be the average of the four people.
- Each of the four spent $y - 12$.
- Fifth person spent $2y - 18$.
Total spent:
$$4(y - 12) + (2y - 18) = 4y - 48 + 2y - 18 = 6y - 66$$
Average of all five:
$$\frac{6y - 66}{5} = y$$
Multiply both sides by 5:
$$6y - 66 = 5y$$
$$6y - 5y = 66$$
$$y = 66$$
So average of four people is 66.
Amounts:
- Four people: $66 - 12 = 54$
- Fifth person: $2(66) - 18 = 132 - 18 = 114$
Total:
$$4 imes 54 + 114 = 216 + 114 = 330$$
Average of all five:
$$330 / 5 = 66$$
11. **Conclusion:** The fifth person spent 114, which is not in the options. Possibly a typo in options or problem.
**Final answer:** The fifth person spent $114$.
Restaurant Spending
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