sandy wrote:

A desert outpost has a water supply that is sufficient to last 21 days for 15 people. At the same average rate of water consumption per person, how many

days would the water supply last for 9 people?

A 28.0

B 32.5

C 35.0

D 37.5

E 42.0

Let's assign a "nice value" to the amount of water that's available.

Let's first say that each person drinks

1 liter of water EACH DAY.

At that rate, the 15 people would drink a total of 15 liters EACH DAY.

So, in 21 days, they'd drink a total of

315 liters

[since (15)(21) = 315].

Now let's see how long that

315 liters of water will last if there are only 9 people.

If each person drinks

1 liter of water EACH DAY, then the 9 people would drink a total of 9 liters EACH DAY.

So, the number of days it takes to drink all

315 =

315/9 = 35

Answer: C

Cheers,

Brent

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Brent Hanneson – Creator of greenlighttestprep.com

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