Add 81/90 and 30/42
81/90 + 30/42 is 113/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 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 42 × 15 = 630,
30/42 = 30 × 15/42 × 15 = 450/630 - Add the two like fractions:
567/630 + 450/630 = 567 + 450/630 = 1017/630 - 1017/630 simplified gives 113/70
- So, 81/90 + 30/42 = 113/70
In mixed form: 143/70
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