Add 20/63 and 70/90
20/63 + 70/90 is 23/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
20/63 = 20 × 10/63 × 10 = 200/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630 - Add the two like fractions:
200/630 + 490/630 = 200 + 490/630 = 690/630 - 690/630 simplified gives 23/21
- So, 20/63 + 70/90 = 23/21
In mixed form: 12/21
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