Add 21/5 and 42/40
1st number: 4 1/5, 2nd number: 1 2/40
21/5 + 42/40 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 5 × 8 = 40,
21/5 = 21 × 8/5 × 8 = 168/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
42/40 = 42 × 1/40 × 1 = 42/40 - Add the two like fractions:
168/40 + 42/40 = 168 + 42/40 = 210/40 - 210/40 simplified gives 21/4
- So, 21/5 + 42/40 = 21/4
In mixed form: 51/4
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