Add 12/90 and 42/21
1st number: 12/90, 2nd number: 2 0/21
12/90 + 42/21 is 32/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
12/90 = 12 × 7/90 × 7 = 84/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630 - Add the two like fractions:
84/630 + 1260/630 = 84 + 1260/630 = 1344/630 - 1344/630 simplified gives 32/15
- So, 12/90 + 42/21 = 32/15
In mixed form: 22/15
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