Explain the concept of regression to the mean between generations

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