Add 84/90 and 12/42
84/90 + 12/42 is 128/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
84/90 = 84 × 7/90 × 7 = 588/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
12/42 = 12 × 15/42 × 15 = 180/630 - Add the two like fractions:
588/630 + 180/630 = 588 + 180/630 = 768/630 - 768/630 simplified gives 128/105
- So, 84/90 + 12/42 = 128/105
In mixed form: 123/105
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