ASVAB (Armed Services Vocational Aptitude Battery)Arithmetic Reasoning (AR)Medium
A military base's water tower holds 50,000 gallons. If the base uses 1,200 gallons per day, and a resupply ship can bring 8,000 gallons every 5 days, after how many days will the water tower be empty if no resupply occurs?
- A41 days
- B40 days
- C35 days
- D42 days
Show answer & explanationAnswer & explanation
Correct answer: A. 41 days
This question asks for the time until empty *if no resupply occurs*. So, simply divide the total capacity by the daily usage: 50,000 gallons / 1,200 gallons/day = 41.66 days. Since it asks 'after how many days', on the 41st day it's not empty, but on the 42nd it will be. However, the exact calculation yields 41.66, meaning it will last for 41 full days and part of the 42nd. Therefore, the tower will be empty *after* 41 days (on the 42nd day). The closest full day before it runs out is 41 days.
Why the other options are wrong
- B. Incorrect, likely a miscalculation of the division.
- C. Incorrect; this would be if the usage was higher or capacity lower.
- D. Incorrect, overestimates the duration before emptying.
Days to Empty Calculation
Determining the number of days a supply will last given a starting quantity and a daily consumption rate.
- Calculated by dividing total quantity by daily rate.
- Any resupply information is a distractor if the question specifies 'no resupply'.
Memory trick: Total in the tank, daily drain, how long till the last rain?