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Explanation:
Water leaks out at a rate of 3 gallons for every 2 days. The unit rate is 3/2 = 1.5 gallons per day that's leaked out.
Let x be the number of days. After x days, the container leaks a total of 1.5x gallons of water. Set this equal to 75 and solve for x. We'll divide both sides by 1.5
1.5x = 75
x = 75/(1.5)
x = 50
It takes 50 days for the container to empty.
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Here's another way to solve:
(3 gallons leaked)/(2 days) = (75 gallons leaked)/(x days)
3/2 = 75/x
3x = 2*75 .... cross multiply
3x = 150
x = 150/3
x = 50 days
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Yet another way to solve:
3 gallons : 2 days
25*(3 gallons) : 25*(2 days) ..... multiply both parts by 25
75 gallons : 50 days
We multiplied by 25 to get that "3 gallons" to "75 gallons". You can use trial and error, or note that 75/3 = 25.
