Add 20/40 and 2/21
20/40 + 2/21 is 25/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
2/21 = 2 × 40/21 × 40 = 80/840 - Add the two like fractions:
420/840 + 80/840 = 420 + 80/840 = 500/840 - 500/840 simplified gives 25/42
- So, 20/40 + 2/21 = 25/42
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