Subtract 21/42 from 40/10
1st number: 4 0/10, 2nd number: 21/42
40/10 - 21/42 is 7/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
40/10 = 40 × 21/10 × 21 = 840/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Subtract the two like fractions:
840/210 - 105/210 = 840 - 105/210 = 735/210 - After reducing the fraction, the answer is 7/2
- In mixed form: 31/2
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