Question

A body of water is being drained it begins with 700 gallons of water and is draining 6.5 gallons each hour .If there are now 388 gallons then for how many hours has it been draining

Answer 1

Therefore it has been draining 48 hours.

Explanation:

Given that a water body is being drained it begins with 700 gallons of water.

Let after x hours the amount of water in the water body will 388 gallons.

The water body is draining 6.5 gallons each hour

It means

The amount of water that drain in 1 hour is 6.5 gallons.

The amount of water that drain in 2 hour is (6.5+6.5) gallons.

=(2×6.5)gallons.

The amount of water that drain in 3 hour is( 6.5+6.5+6.5) gallons.

=(3×6.5) gallons.

Therefore

The amount of water that drain = time ×6.5

The amount of water that drain in x hour is (x×6.5) gallons=6.5x gallons.

Therefore the remaining water

= initial amount of water- drainage water

=(700-6.5x)gallons

According to the problem,

700-6.5x= 388

⇒ -6.5x = 388-700

⇒ - 6.5x = - 312

`\Rightarrow x=(-312)/(-6.5)`

⇒ x= 48

Therefore it has been draining 48 hours.