Add 72/21 and 63/90
1st number: 3 9/21, 2nd number: 63/90
72/21 + 63/90 is 289/70.
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,
63/90 = 63 × 7/90 × 7 = 441/630 - Add the two like fractions:
2160/630 + 441/630 = 2160 + 441/630 = 2601/630 - 2601/630 simplified gives 289/70
- So, 72/21 + 63/90 = 289/70
In mixed form: 49/70
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