Add 21/2 and 40/72, Solve 10 1/2 + 40/72 as a fraction

Add 21/2 and 40/72

1^st number: 10 1/2, 2^nd number: 40/72

21/2 + 40/72 is 199/18.

Find the least common denominator or LCM of the two denominators:
LCM of 2 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 2 × 36 = 72,
21/2 = 21 × 36/2 × 36 = 756/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
40/72 = 40 × 1/72 × 1 = 40/72
Add the two like fractions:
756/72 + 40/72 = 756 + 40/72 = 796/72
796/72 simplified gives 199/18
So, 21/2 + 40/72 = 199/18
In mixed form: 111/18

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