Add 21/42 and 7/20
21/42 + 7/20 is 17/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
21/42 = 21 × 10/42 × 10 = 210/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
7/20 = 7 × 21/20 × 21 = 147/420 - Add the two like fractions:
210/420 + 147/420 = 210 + 147/420 = 357/420 - 357/420 simplified gives 17/20
- So, 21/42 + 7/20 = 17/20
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