Add 20/40 and 81/84
20/40 + 81/84 is 41/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 84 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
20/40 = 20 × 21/40 × 21 = 420/840 - Likewise, for the 2nd fraction, since 84 × 10 = 840,
81/84 = 81 × 10/84 × 10 = 810/840 - Add the two like fractions:
420/840 + 810/840 = 420 + 810/840 = 1230/840 - 1230/840 simplified gives 41/28
- So, 20/40 + 81/84 = 41/28
In mixed form: 113/28
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