Add 21/18 and 45/70
1st number: 1 3/18, 2nd number: 45/70
21/18 + 45/70 is 38/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 70 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 18 × 35 = 630,
21/18 = 21 × 35/18 × 35 = 735/630 - Likewise, for the 2nd fraction, since 70 × 9 = 630,
45/70 = 45 × 9/70 × 9 = 405/630 - Add the two like fractions:
735/630 + 405/630 = 735 + 405/630 = 1140/630 - 1140/630 simplified gives 38/21
- So, 21/18 + 45/70 = 38/21
In mixed form: 117/21
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