Add 21/60 and 28/70
21/60 + 28/70 is 3/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 60 × 7 = 420,
21/60 = 21 × 7/60 × 7 = 147/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
28/70 = 28 × 6/70 × 6 = 168/420 - Add the two like fractions:
147/420 + 168/420 = 147 + 168/420 = 315/420 - 315/420 simplified gives 3/4
- So, 21/60 + 28/70 = 3/4
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