Add 21/84 and 42/75
21/84 + 42/75 is 81/100.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 75 is 2100
Next, find the equivalent fraction of both fractional numbers with denominator 2100 - For the 1st fraction, since 84 × 25 = 2100,
21/84 = 21 × 25/84 × 25 = 525/2100 - Likewise, for the 2nd fraction, since 75 × 28 = 2100,
42/75 = 42 × 28/75 × 28 = 1176/2100 - Add the two like fractions:
525/2100 + 1176/2100 = 525 + 1176/2100 = 1701/2100 - 1701/2100 simplified gives 81/100
- So, 21/84 + 42/75 = 81/100
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