Add 27/90 and 12/21
27/90 + 12/21 is 61/70.
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,
27/90 = 27 × 7/90 × 7 = 189/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
12/21 = 12 × 30/21 × 30 = 360/630 - Add the two like fractions:
189/630 + 360/630 = 189 + 360/630 = 549/630 - 549/630 simplified gives 61/70
- So, 27/90 + 12/21 = 61/70
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