Subtract 90/50 from 90/70
1st number: 1 20/70, 2nd number: 1 40/50
90/70 - 90/50 is -18/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 50 is 350
Next, find the equivalent fraction of both fractional numbers with denominator 350 - For the 1st fraction, since 70 × 5 = 350,
90/70 = 90 × 5/70 × 5 = 450/350 - Likewise, for the 2nd fraction, since 50 × 7 = 350,
90/50 = 90 × 7/50 × 7 = 630/350 - Subtract the two like fractions:
450/350 - 630/350 = 450 - 630/350 = -180/350 - After reducing the fraction, the answer is -18/35
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