What is the lowest score she needs?

Laura is bowling 5 games. Her first 4 scores were 96, 133, 94, and 132. To end up with an average score of at least 119.4, what is the lowest score Laura will need in the fifth game?

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To find the average of a set of numbers, add the numbers up and divide by the number of numbers.

Here, add the 4 scores up plus a missing score, x, and divide by 5, setting all of this to be greater than or equal to the average, 119.4, since you’re looking for the lowest score she needs on the fifth game. Then, solve for x to find that least score.

96 + 133 + 94 + 132 + x
————————————— = 119.4
                5

455 + x
————— = 119.4 {added the numbers in the numerator}
      5

455 + x ≥ 597 {multiplied each side by 5}

x ≥ 142 {subtracted 455 from each side}

The lowest score needed is 142.

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