Add 5/20 and 42/21
1st number: 5/20, 2nd number: 2 0/21
5/20 + 42/21 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
5/20 = 5 × 21/20 × 21 = 105/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Add the two like fractions:
105/420 + 840/420 = 105 + 840/420 = 945/420 - 945/420 simplified gives 9/4
- So, 5/20 + 42/21 = 9/4
In mixed form: 21/4
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