Add 42/60 and 9/21
42/60 + 9/21 is 79/70.
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,
9/21 = 9 × 20/21 × 20 = 180/420 - Add the two like fractions:
294/420 + 180/420 = 294 + 180/420 = 474/420 - 474/420 simplified gives 79/70
- So, 42/60 + 9/21 = 79/70
In mixed form: 19/70
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