Add 15/90 and 30/21
1st number: 15/90, 2nd number: 1 9/21
15/90 + 30/21 is 67/42.
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,
15/90 = 15 × 7/90 × 7 = 105/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
30/21 = 30 × 30/21 × 30 = 900/630 - Add the two like fractions:
105/630 + 900/630 = 105 + 900/630 = 1005/630 - 1005/630 simplified gives 67/42
- So, 15/90 + 30/21 = 67/42
In mixed form: 125/42
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