Mary earns $20 washing cars and $40 walking dogs each month. If she puts half of that money away each month how long would it take her to save $150?
Think hard. Detailed solution:
5
Each month she makes 20 + 40 = $60.

Every month she saves 60 / 2 = $30.

To save $150 it will take her 150 / 30 = 5 months.

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The final answer: 5