Add 81/90 and 20/63
81/90 + 20/63 is 767/630.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
20/63 = 20 × 10/63 × 10 = 200/630 - Add the two like fractions:
567/630 + 200/630 = 567 + 200/630 = 767/630 - So, 81/90 + 20/63 = 767/630
In mixed form: 1137/630
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