Add 21/60 and 21/70
21/60 + 21/70 is 13/20.
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,
21/70 = 21 × 6/70 × 6 = 126/420 - Add the two like fractions:
147/420 + 126/420 = 147 + 126/420 = 273/420 - 273/420 simplified gives 13/20
- So, 21/60 + 21/70 = 13/20
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