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Solving Inequalities Using Addition, Subtraction, Multiplication and Division, a la Shmoop.

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The local aquarium is throwing a Save the Blobfish fundraiser. [Man and little girl looking at fish in an aquarium]

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No one cares about the poor blobfish...

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Only cute animals get love. You and your friend want to save the blobfish. [Friends stood with a blobfish]

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But no one else shows up.

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Your oh so generous mom gave you $6 to contribute to the fund. She loves the blobfish. [Mother gives 6 dollars to save the blobfish]

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Unfortunately, the fundraiser doesn't allow total donations more than $30, thanks to tax regulations.

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What is the most amount of money you and your friend can each contribute?

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We may not be able to save the blobfish... [Blobfish flushed down a toilet]

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But we can solve this problem.

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Let's let x be the maximum amount of money you and your friend can EACH contribute,

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Since both of you are contributing x dollars, we can write that as 2x.

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And don't forget your mom's generous $6 donation to the cause.

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So the total we can contribute is 2x + 6.

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BUT the maximum we can donate is $30, so 2x + 6 is less than or equal to 30. [Maths formula shown and Uncle Sam appears]

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Now to solve this pressing issue.

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First we'll subtract six from each side...

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That leaves us with 2x is less than or equal to 24.

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Now we need to divide both sides by two.

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That gives us x is less than or equal to 12. So you and your friend can each contribute $12. [Two friends contributing 12 dollars to save blobfish]

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You'll either have to get more friends to

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donate money or ask the president to change the tax regulations. Good luck with that..

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Starving blobfish in the Pacific need your help today. [Blobfish holding up a sign to work for krill]

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