Acandy bar weighing 4 ounces costs 'c' cents. if the size of the candy bar is reduced to 3.6 ounces while the price remains the same, the old price per ounce is what fraction of the new price per ounce?

The old price per ounce is c/4.

The new price per ounce is c/3.6.

The ratio of the old price to the new one is

... (c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . . . = 9/10 . . . "nine tenths" in either form

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