Add 15/21 and 40/90
15/21 + 40/90 is 73/63.
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,
15/21 = 15 × 30/21 × 30 = 450/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
40/90 = 40 × 7/90 × 7 = 280/630 - Add the two like fractions:
450/630 + 280/630 = 450 + 280/630 = 730/630 - 730/630 simplified gives 73/63
- So, 15/21 + 40/90 = 73/63
In mixed form: 110/63
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