Subtract 7/40 from 90/42, Solve 2 6/42

Subtract 7/40 from 90/42

1^st number: 2 6/42, 2^nd number: 7/40

90/42 - 7/40 is 551/280.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
90/42 = 90 × 20/42 × 20 = 1800/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
7/40 = 7 × 21/40 × 21 = 147/840
Subtract the two like fractions:
1800/840 - 147/840 = 1800 - 147/840 = 1653/840
After reducing the fraction, the answer is 551/280
In mixed form: 1271/280

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