Add 15/21 and 28/90
15/21 + 28/90 is 323/315.
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,
15/21 = 15 × 30/21 × 30 = 450/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
28/90 = 28 × 7/90 × 7 = 196/630 - Add the two like fractions:
450/630 + 196/630 = 450 + 196/630 = 646/630 - 646/630 simplified gives 323/315
- So, 15/21 + 28/90 = 323/315
In mixed form: 18/315
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