Add 90/21 and 42/20
1st number: 4 6/21, 2nd number: 2 2/20
90/21 + 42/20 is 447/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
90/21 = 90 × 20/21 × 20 = 1800/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
42/20 = 42 × 21/20 × 21 = 882/420 - Add the two like fractions:
1800/420 + 882/420 = 1800 + 882/420 = 2682/420 - 2682/420 simplified gives 447/70
- So, 90/21 + 42/20 = 447/70
In mixed form: 627/70
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