Add 72/21 and 81/90
1st number: 3 9/21, 2nd number: 81/90
72/21 + 81/90 is 303/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
72/21 = 72 × 30/21 × 30 = 2160/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Add the two like fractions:
2160/630 + 567/630 = 2160 + 567/630 = 2727/630 - 2727/630 simplified gives 303/70
- So, 72/21 + 81/90 = 303/70
In mixed form: 423/70
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