Add 40/3 and 21/40, Solve 13 1/3 + 21/40 as a fraction

Add 40/3 and 21/40

1^st number: 13 1/3, 2^nd number: 21/40

40/3 + 21/40 is 1663/120.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 40 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 3 × 40 = 120,
40/3 = 40 × 40/3 × 40 = 1600/120
Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120
Add the two like fractions:
1600/120 + 63/120 = 1600 + 63/120 = 1663/120
So, 40/3 + 21/40 = 1663/120
In mixed form: 13103/120

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