Subtract 1/72 from 90/70, Solve 1 20/70

Subtract 1/72 from 90/70

1^st number: 1 20/70, 2^nd number: 1/72

90/70 - 1/72 is 641/504.

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,
1/72 = 1 × 35/72 × 35 = 35/2520
Subtract the two like fractions:
3240/2520 - 35/2520 = 3240 - 35/2520 = 3205/2520
After reducing the fraction, the answer is 641/504
In mixed form: 1137/504

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