Add 3/90 and 5/21
3/90 + 5/21 is 19/70.
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,
3/90 = 3 × 7/90 × 7 = 21/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
5/21 = 5 × 30/21 × 30 = 150/630 - Add the two like fractions:
21/630 + 150/630 = 21 + 150/630 = 171/630 - 171/630 simplified gives 19/70
- So, 3/90 + 5/21 = 19/70
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