Each time Ali sharpened her pencil, it was shortened by 0.52 cm. After she had sharpened it 8 times, it was 4.89 cm.
What was its original length? (Give your answer correct to 1 decimal place.)

Answer: B. 9.1

Ali lost a total of 4.16 cm of pencil from sharpening it 8 times ( 8 x 0.52).
Adding that lost amount back to the final length gives 9.05 cm (4.89 + 4.16).
To round to one decimal place, look at the 5 in 9.05 and round the previous digit up.
The original length of the pencil was 9.1 cm

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