Add 21/90 and 7/21
21/90 + 7/21 is 17/30.
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,
21/90 = 21 × 7/90 × 7 = 147/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
7/21 = 7 × 30/21 × 30 = 210/630 - Add the two like fractions:
147/630 + 210/630 = 147 + 210/630 = 357/630 - 357/630 simplified gives 17/30
- So, 21/90 + 7/21 = 17/30
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