Add 45/21 and 20/90
1st number: 2 3/21, 2nd number: 20/90
45/21 + 20/90 is 149/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 21 × 30 = 630,
45/21 = 45 × 30/21 × 30 = 1350/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Add the two like fractions:
1350/630 + 140/630 = 1350 + 140/630 = 1490/630 - 1490/630 simplified gives 149/63
- So, 45/21 + 20/90 = 149/63
In mixed form: 223/63
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