Add 42/21 and 90/20
1st number: 2 0/21, 2nd number: 4 10/20
42/21 + 90/20 is 13/2.
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,
42/21 = 42 × 20/21 × 20 = 840/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
90/20 = 90 × 21/20 × 21 = 1890/420 - Add the two like fractions:
840/420 + 1890/420 = 840 + 1890/420 = 2730/420 - 2730/420 simplified gives 13/2
- So, 42/21 + 90/20 = 13/2
In mixed form: 61/2
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