Add 42/21 and 20/90
1st number: 2 0/21, 2nd number: 20/90
42/21 + 20/90 is 20/9.
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,
42/21 = 42 × 30/21 × 30 = 1260/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
20/90 = 20 × 7/90 × 7 = 140/630 - Add the two like fractions:
1260/630 + 140/630 = 1260 + 140/630 = 1400/630 - 1400/630 simplified gives 20/9
- So, 42/21 + 20/90 = 20/9
In mixed form: 22/9
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