Add 18/21 and 42/60
18/21 + 42/60 is 109/70.
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,
18/21 = 18 × 20/21 × 20 = 360/420 - Likewise, for the 2nd fraction, since 60 × 7 = 420,
42/60 = 42 × 7/60 × 7 = 294/420 - Add the two like fractions:
360/420 + 294/420 = 360 + 294/420 = 654/420 - 654/420 simplified gives 109/70
- So, 18/21 + 42/60 = 109/70
In mixed form: 139/70
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