Add 42/84 and 21/5
1st number: 42/84, 2nd number: 4 1/5
42/84 + 21/5 is 47/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 5 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
42/84 = 42 × 5/84 × 5 = 210/420 - Likewise, for the 2nd fraction, since 5 × 84 = 420,
21/5 = 21 × 84/5 × 84 = 1764/420 - Add the two like fractions:
210/420 + 1764/420 = 210 + 1764/420 = 1974/420 - 1974/420 simplified gives 47/10
- So, 42/84 + 21/5 = 47/10
In mixed form: 47/10
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