Add 5/21 and 72/90
5/21 + 72/90 is 109/105.
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,
5/21 = 5 × 30/21 × 30 = 150/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
72/90 = 72 × 7/90 × 7 = 504/630 - Add the two like fractions:
150/630 + 504/630 = 150 + 504/630 = 654/630 - 654/630 simplified gives 109/105
- So, 5/21 + 72/90 = 109/105
In mixed form: 14/105
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