1968 AMC 12 Problem 8

Attempt Problem 8 of the 1968 AMC 12 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1968 AMC 12 solutions, or check the answer key.

All problems are used with official legal permission of the Mathematical Association of America (MAA).

A positive number is mistakenly divided by

6

instead of being multiplied by

6.

Based on the correct answer, the error thus committed, to the nearest percent, is:

100

97

83

17

3

Let the number be

N

and compare

\frac{N}{6}

with

6N

Divide the absolute error by the correct result

The correct result is

6N,

while the mistaken result is

\frac{N}{6}.

Relative to the correct result, the error is

\frac{6N-\frac{N}{6}}{6N}=\frac{35}{36}\approx97.2\%.

Therefore, the correct answer is B.

Problem 8 in other years