Subtract 1/40 from 21/9, Solve 2 3/9

Subtract 1/40 from 21/9

1^st number: 2 3/9, 2^nd number: 1/40

21/9 - 1/40 is 277/120.

Find the least common denominator or LCM of the two denominators:
LCM of 9 and 40 is 360

Next, find the equivalent fraction of both fractional numbers with denominator 360
For the 1st fraction, since 9 × 40 = 360,
21/9 = 21 × 40/9 × 40 = 840/360
Likewise, for the 2nd fraction, since 40 × 9 = 360,
1/40 = 1 × 9/40 × 9 = 9/360
Subtract the two like fractions:
840/360 - 9/360 = 840 - 9/360 = 831/360
After reducing the fraction, the answer is 277/120
In mixed form: 237/120

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