Add 72/90 and 15/21
72/90 + 15/21 is 53/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
15/21 = 15 × 30/21 × 30 = 450/630 - Add the two like fractions:
504/630 + 450/630 = 504 + 450/630 = 954/630 - 954/630 simplified gives 53/35
- So, 72/90 + 15/21 = 53/35
In mixed form: 118/35
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