Add 7/21 and 9/90
7/21 + 9/90 is 13/30.
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,
7/21 = 7 × 30/21 × 30 = 210/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
9/90 = 9 × 7/90 × 7 = 63/630 - Add the two like fractions:
210/630 + 63/630 = 210 + 63/630 = 273/630 - 273/630 simplified gives 13/30
- So, 7/21 + 9/90 = 13/30
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