Subtract 3/72 from 90/70
1st number: 1 20/70, 2nd number: 3/72
90/70 - 3/72 is 209/168.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520
Next, find the equivalent fraction of both fractional numbers with denominator 2520 - For the 1st fraction, since 70 × 36 = 2520,
90/70 = 90 × 36/70 × 36 = 3240/2520 - Likewise, for the 2nd fraction, since 72 × 35 = 2520,
3/72 = 3 × 35/72 × 35 = 105/2520 - Subtract the two like fractions:
3240/2520 - 105/2520 = 3240 - 105/2520 = 3135/2520 - After reducing the fraction, the answer is 209/168
- In mixed form: 141/168
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