Add 3/21 and 4/40
3/21 + 4/40 is 17/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
3/21 = 3 × 40/21 × 40 = 120/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
4/40 = 4 × 21/40 × 21 = 84/840 - Add the two like fractions:
120/840 + 84/840 = 120 + 84/840 = 204/840 - 204/840 simplified gives 17/70
- So, 3/21 + 4/40 = 17/70
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