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natita [175]
3 years ago
9

A water tank holds 486 gallons but leaking at a rate 4 gallons per week. A second water tank holds 648 gallons but is leaking at

a rate of 7 gallons per week. After how many weeks will the amount of water in the 2 tanks? The amount of water that holds the two tanks will be the same in _ weeks.
Mathematics
1 answer:
notka56 [123]3 years ago
6 0

The first tank contains

486 gal - (4 gal/week) <em>t</em>

gal of water after <em>t</em> weeks.

Similarly, the second tank contains

648 gal - (7 gal/week) <em>t</em>

gal of water.

The tanks hold the same amount of water when these two amounts are equal:

486 gal - (4 gal/week) <em>t</em> = 648 gal - (7 gal/week) <em>t</em>

(7 gal/week) <em>t</em> - (4 gal/week) <em>t</em> = 648 gal - 486 gal

(3 gal/week) <em>t</em> = 162 gal

<em>t</em> = (162 gal) / (3 gal/week)

<em>t</em> = 54 weeks

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