Subtract 30/80 from 9/10
9/10 - 30/80 is 21/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 10 × 8 = 80,
9/10 = 9 × 8/10 × 8 = 72/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80 - Subtract the two like fractions:
72/80 - 30/80 = 72 - 30/80 = 42/80 - After reducing the fraction, the answer is 21/40
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