Add 7/21 and 40/84
7/21 + 40/84 is 17/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
7/21 = 7 × 4/21 × 4 = 28/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
40/84 = 40 × 1/84 × 1 = 40/84 - Add the two like fractions:
28/84 + 40/84 = 28 + 40/84 = 68/84 - 68/84 simplified gives 17/21
- So, 7/21 + 40/84 = 17/21
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