Subtract 30/21 from 70/72
1st number: 70/72, 2nd number: 1 9/21
70/72 - 30/21 is -115/252.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
70/72 = 70 × 7/72 × 7 = 490/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
30/21 = 30 × 24/21 × 24 = 720/504 - Subtract the two like fractions:
490/504 - 720/504 = 490 - 720/504 = -230/504 - After reducing the fraction, the answer is -115/252
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