Add 40/28 and 90/21
1st number: 1 12/28, 2nd number: 4 6/21
40/28 + 90/21 is 40/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
40/28 = 40 × 3/28 × 3 = 120/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Add the two like fractions:
120/84 + 360/84 = 120 + 360/84 = 480/84 - 480/84 simplified gives 40/7
- So, 40/28 + 90/21 = 40/7
In mixed form: 55/7
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