Add 21/70 and 28/63
21/70 + 28/63 is 67/90.
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,
28/63 = 28 × 10/63 × 10 = 280/630 - Add the two like fractions:
189/630 + 280/630 = 189 + 280/630 = 469/630 - 469/630 simplified gives 67/90
- So, 21/70 + 28/63 = 67/90
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