Add 42/24 and 54/21
1st number: 1 18/24, 2nd number: 2 12/21
42/24 + 54/21 is 121/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 24 × 7 = 168,
42/24 = 42 × 7/24 × 7 = 294/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
54/21 = 54 × 8/21 × 8 = 432/168 - Add the two like fractions:
294/168 + 432/168 = 294 + 432/168 = 726/168 - 726/168 simplified gives 121/28
- So, 42/24 + 54/21 = 121/28
In mixed form: 49/28
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