Add 72/42 and 28/90
1st number: 1 30/42, 2nd number: 28/90
72/42 + 28/90 is 638/315.
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,
72/42 = 72 × 15/42 × 15 = 1080/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
28/90 = 28 × 7/90 × 7 = 196/630 - Add the two like fractions:
1080/630 + 196/630 = 1080 + 196/630 = 1276/630 - 1276/630 simplified gives 638/315
- So, 72/42 + 28/90 = 638/315
In mixed form: 28/315
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