Easier way to divide a fraction by a fraction.Say this is the problem: 3 / 8 4 / 5 As of right now, I would multiply both fractions by 40 then simplify to get 15 32 Or I would multiply 3 8 and 5 4 to get the same result.Is there a better way to do this?*In order for me to correctly ask this question, can someone leave a comment below on how to divide a fraction by a fraction using mathJax. Thanks

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Easier way to divide a fraction by a fraction.Say this is the problem:            3              /            8              4              /            5      As of right now, I would multiply both fractions by   40 then simplify to get       15    32  Or I would multiply       3    8   and       5    4   to get the same result.Is there a better way to do this?*In order for me to correctly ask this question, can someone leave a comment below on how to divide a fraction by a fraction using mathJax. Thanks

hi3c4a2nvrgzb · Accepted Answer

A common way is to multiply the dividend by the reciprocal of the divisor:            3              /            8              4              /            5        =      3    8    ÷      4    5    =      3    8    ×      5    4    =            3      ×      5              8      ×      4        =      15    32    .The other way you mention works as well:            3              /            8              4              /            5        =                    3        8            ×      40                      4        5            ×      40        =            120      8              160      5        =      15    32    .What may end up happening if you do it this way is that the fraction won&#039;t be in lowest terms yet and you&#039;ll need to factor the numerator and denominator to get the common factors out. (It is already in lowest terms in this case.) Doing it the first way gives you more of a chance to see common factors in the numerator and denominator that can be canceled since you&#039;ve multiplied less together.But they&#039;ll both get you there, and one isn&#039;t all that much harder than the other.

Alaina Holt · Accepted Answer

You remember the rule to multiply by the reciprical. You remember that the reciprical is just turning the dividing fraction &quot;upside down&quot;. And you remember multiplying is multiplying the numerators together and the denominators together.So            3      8              4      5        =      3    8    ⋅      5    4    =            3      ⋅      5              8      ⋅      4        =      15    32  That&#039;s pretty @@@@ing easy if you ask me. The only easier way I can think of is to ask someone else to do it for you. Which is probably actually significantly harder.

Easier way to divide a fraction by a fraction. Say this is the problem: 3

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