Add 21/60 and 18/70
21/60 + 18/70 is 17/28.
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,
18/70 = 18 × 6/70 × 6 = 108/420 - Add the two like fractions:
147/420 + 108/420 = 147 + 108/420 = 255/420 - 255/420 simplified gives 17/28
- So, 21/60 + 18/70 = 17/28
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