Add 42/60 and 7/21
42/60 + 7/21 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
42/60 = 42 × 7/60 × 7 = 294/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
7/21 = 7 × 20/21 × 20 = 140/420 - Add the two like fractions:
294/420 + 140/420 = 294 + 140/420 = 434/420 - 434/420 simplified gives 31/30
- So, 42/60 + 7/21 = 31/30
In mixed form: 11/30
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