Add 40/84 and 20/21
40/84 + 20/21 is 10/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
40/84 = 40 × 1/84 × 1 = 40/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Add the two like fractions:
40/84 + 80/84 = 40 + 80/84 = 120/84 - 120/84 simplified gives 10/7
- So, 40/84 + 20/21 = 10/7
In mixed form: 13/7
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