#### maninthemirror

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Please help. Need help desperately as my submission is tmr

- Thread starter maninthemirror
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Please help. Need help desperately as my submission is tmr

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This can be solved more easily (in the sense of needing less special thinking) by a little algebra. Have you (or the student) learned any?

Please help. Need help desperately as my submission is tmr

On the other hand, Harry's approach uses number sense well. Since the sum of the numbers is divided by n, anything you add to that sum (in making a correction, for example) is also divided by n.

If you know some algebra, this is a relatively easy problem. As a pure arithmetic problem, it is a nightmare.

\(\displaystyle c = \text {correct total.}\)

\(\displaystyle i = \text {incorrect total.}\)

\(\displaystyle n = \text {number of items.}\)

\(\displaystyle c - i = 153 - 135.\).......................................edited

\(\displaystyle \dfrac{c}{n} - \dfrac{i}{n} = 129 - 124.5.\)

Can you solve it now?

\(\displaystyle c = \text {correct total.}\)

\(\displaystyle i = \text {incorrect total.}\)

\(\displaystyle n = \text {number of items.}\)

\(\displaystyle c - i = 153 - 135.\).......................................edited

\(\displaystyle \dfrac{c}{n} - \dfrac{i}{n} = 129 - 124.5.\)

Can you solve it now?

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What is f?If you know some algebra, this is a relatively easy problem. As a pure arithmetic problem, it is a nightmare.

\(\displaystyle c = \text {correct total.}\)

\(\displaystyle i = \text {incorrect total.}\)

\(\displaystyle n = \text {number of items.}\)

\(\displaystyle c - f = 153 - 135.\)

\(\displaystyle \dfrac{c}{n} - \dfrac{i}{n} = 129 - 124.5.\)

Can you solve it now?

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Yes I was assuming no algebra was involved.