Add 1/90 and 7/21
1/90 + 7/21 is 31/90.
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,
1/90 = 1 × 7/90 × 7 = 7/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
7/21 = 7 × 30/21 × 30 = 210/630 - Add the two like fractions:
7/630 + 210/630 = 7 + 210/630 = 217/630 - 217/630 simplified gives 31/90
- So, 1/90 + 7/21 = 31/90
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