Add 7/42 and 81/90
7/42 + 81/90 is 16/15.
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,
7/42 = 7 × 15/42 × 15 = 105/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Add the two like fractions:
105/630 + 567/630 = 105 + 567/630 = 672/630 - 672/630 simplified gives 16/15
- So, 7/42 + 81/90 = 16/15
In mixed form: 11/15
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