Add 20/84 and 40/70
20/84 + 40/70 is 17/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
20/84 = 20 × 5/84 × 5 = 100/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
40/70 = 40 × 6/70 × 6 = 240/420 - Add the two like fractions:
100/420 + 240/420 = 100 + 240/420 = 340/420 - 340/420 simplified gives 17/21
- So, 20/84 + 40/70 = 17/21
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