Add 21/70 and 18/45
21/70 + 18/45 is 7/10.
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,
18/45 = 18 × 14/45 × 14 = 252/630 - Add the two like fractions:
189/630 + 252/630 = 189 + 252/630 = 441/630 - 441/630 simplified gives 7/10
- So, 21/70 + 18/45 = 7/10
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