Add 81/90 and 20/49
81/90 + 20/49 is 641/490.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 49 is 4410
Next, find the equivalent fraction of both fractional numbers with denominator 4410 - For the 1st fraction, since 90 × 49 = 4410,
81/90 = 81 × 49/90 × 49 = 3969/4410 - Likewise, for the 2nd fraction, since 49 × 90 = 4410,
20/49 = 20 × 90/49 × 90 = 1800/4410 - Add the two like fractions:
3969/4410 + 1800/4410 = 3969 + 1800/4410 = 5769/4410 - 5769/4410 simplified gives 641/490
- So, 81/90 + 20/49 = 641/490
In mixed form: 1151/490
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