Add 81/90 and 18/70
81/90 + 18/70 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 70 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 70 × 9 = 630,
18/70 = 18 × 9/70 × 9 = 162/630 - Add the two like fractions:
567/630 + 162/630 = 567 + 162/630 = 729/630 - 729/630 simplified gives 81/70
- So, 81/90 + 18/70 = 81/70
In mixed form: 111/70
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