Add 81/70 and 21/90
1st number: 1 11/70, 2nd number: 21/90
81/70 + 21/90 is 146/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
81/70 = 81 × 9/70 × 9 = 729/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
729/630 + 147/630 = 729 + 147/630 = 876/630 - 876/630 simplified gives 146/105
- So, 81/70 + 21/90 = 146/105
In mixed form: 141/105
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