Add 81/42 and 1/90
1st number: 1 39/42, 2nd number: 1/90
81/42 + 1/90 is 611/315.
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,
81/42 = 81 × 15/42 × 15 = 1215/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
1/90 = 1 × 7/90 × 7 = 7/630 - Add the two like fractions:
1215/630 + 7/630 = 1215 + 7/630 = 1222/630 - 1222/630 simplified gives 611/315
- So, 81/42 + 1/90 = 611/315
In mixed form: 1296/315
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