Add 15/21 and 42/60
15/21 + 42/60 is 99/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 60 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
15/21 = 15 × 20/21 × 20 = 300/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
42/60 = 42 × 7/60 × 7 = 294/420 - Add the two like fractions:
300/420 + 294/420 = 300 + 294/420 = 594/420 - 594/420 simplified gives 99/70
- So, 15/21 + 42/60 = 99/70
In mixed form: 129/70
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