Add 3/21 and 21/90
3/21 + 21/90 is 79/210.
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,
3/21 = 3 × 30/21 × 30 = 90/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
90/630 + 147/630 = 90 + 147/630 = 237/630 - 237/630 simplified gives 79/210
- So, 3/21 + 21/90 = 79/210
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