Add 20/75 and 70/21
1st number: 20/75, 2nd number: 3 7/21
20/75 + 70/21 is 18/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 21 is 525
Next, find the equivalent fraction of both fractional numbers with denominator 525 - For the 1st fraction, since 75 × 7 = 525,
20/75 = 20 × 7/75 × 7 = 140/525 - Likewise, for the 2nd fraction, since 21 × 25 = 525,
70/21 = 70 × 25/21 × 25 = 1750/525 - Add the two like fractions:
140/525 + 1750/525 = 140 + 1750/525 = 1890/525 - 1890/525 simplified gives 18/5
- So, 20/75 + 70/21 = 18/5
In mixed form: 33/5
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