Add 15/42 and 75/90
15/42 + 75/90 is 25/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
15/42 = 15 × 15/42 × 15 = 225/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
75/90 = 75 × 7/90 × 7 = 525/630 - Add the two like fractions:
225/630 + 525/630 = 225 + 525/630 = 750/630 - 750/630 simplified gives 25/21
- So, 15/42 + 75/90 = 25/21
In mixed form: 14/21
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