Add 90/21 and 90/42
1st number: 4 6/21, 2nd number: 2 6/42
90/21 + 90/42 is 45/7.
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,
90/21 = 90 × 2/21 × 2 = 180/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
90/42 = 90 × 1/42 × 1 = 90/42 - Add the two like fractions:
180/42 + 90/42 = 180 + 90/42 = 270/42 - 270/42 simplified gives 45/7
- So, 90/21 + 90/42 = 45/7
In mixed form: 63/7
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