Add 75/21 and 90/42
1st number: 3 12/21, 2nd number: 2 6/42
75/21 + 90/42 is 40/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
75/21 = 75 × 2/21 × 2 = 150/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
90/42 = 90 × 1/42 × 1 = 90/42 - Add the two like fractions:
150/42 + 90/42 = 150 + 90/42 = 240/42 - 240/42 simplified gives 40/7
- So, 75/21 + 90/42 = 40/7
In mixed form: 55/7
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