Add 21/90 and 12/63
21/90 + 12/63 is 89/210.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 63 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 63 × 10 = 630,
12/63 = 12 × 10/63 × 10 = 120/630 - Add the two like fractions:
147/630 + 120/630 = 147 + 120/630 = 267/630 - 267/630 simplified gives 89/210
- So, 21/90 + 12/63 = 89/210
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