Add 21/70 and 28/45
21/70 + 28/45 is 83/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 45 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 45 × 14 = 630,
28/45 = 28 × 14/45 × 14 = 392/630 - Add the two like fractions:
189/630 + 392/630 = 189 + 392/630 = 581/630 - 581/630 simplified gives 83/90
- So, 21/70 + 28/45 = 83/90
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