Add 21/70 and 56/63
21/70 + 56/63 is 107/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
56/63 = 56 × 10/63 × 10 = 560/630 - Add the two like fractions:
189/630 + 560/630 = 189 + 560/630 = 749/630 - 749/630 simplified gives 107/90
- So, 21/70 + 56/63 = 107/90
In mixed form: 117/90
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