Add 7/21 and 21/90
7/21 + 21/90 is 17/30.
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,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
210/630 + 147/630 = 210 + 147/630 = 357/630 - 357/630 simplified gives 17/30
- So, 7/21 + 21/90 = 17/30
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