Add 20/5 and 45/21
1st number: 4 0/5, 2nd number: 2 3/21
20/5 + 45/21 is 43/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
20/5 = 20 × 21/5 × 21 = 420/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
45/21 = 45 × 5/21 × 5 = 225/105 - Add the two like fractions:
420/105 + 225/105 = 420 + 225/105 = 645/105 - 645/105 simplified gives 43/7
- So, 20/5 + 45/21 = 43/7
In mixed form: 61/7
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