a contractor estimates he will need 18 sheets of drywall and 65 square feet of tile to remodel a bathroom. He actually uses 14 sheets of drywall and 42 square feet of tile. To the nearest percent, what is the difference in the percent errors of the estimates?

let x be the money she spent so that she can earn the free t-shirt.

since, she already spent $112.49

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also, as per the statement: jennifer must spend $250 or more in order to qualify for a free t-shirt at the store.

then,

we have an inequality i.,e

subtract 112.49 from both sides we get;

therefore, $137. 51 more money does jennifer need to spend so that she can earn the free t-shirt

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

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