Add 21/84 and 16/40
21/84 + 16/40 is 13/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
21/84 = 21 × 10/84 × 10 = 210/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
16/40 = 16 × 21/40 × 21 = 336/840 - Add the two like fractions:
210/840 + 336/840 = 210 + 336/840 = 546/840 - 546/840 simplified gives 13/20
- So, 21/84 + 16/40 = 13/20
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