Add 42/18 and 90/21
1st number: 2 6/18, 2nd number: 4 6/21
42/18 + 90/21 is 139/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
42/18 = 42 × 7/18 × 7 = 294/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126 - Add the two like fractions:
294/126 + 540/126 = 294 + 540/126 = 834/126 - 834/126 simplified gives 139/21
- So, 42/18 + 90/21 = 139/21
In mixed form: 613/21
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