Add 12/42 and 81/90
12/42 + 81/90 is 83/70.
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,
12/42 = 12 × 15/42 × 15 = 180/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
81/90 = 81 × 7/90 × 7 = 567/630 - Add the two like fractions:
180/630 + 567/630 = 180 + 567/630 = 747/630 - 747/630 simplified gives 83/70
- So, 12/42 + 81/90 = 83/70
In mixed form: 113/70
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