Add 21/40 and 45/6, Solve 21/40 + 7 3/6 as a fraction

Add 21/40 and 45/6

1^st number: 21/40, 2^nd number: 7 3/6

21/40 + 45/6 is 321/40.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 6 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120
Likewise, for the 2nd fraction, since 6 × 20 = 120,
45/6 = 45 × 20/6 × 20 = 900/120
Add the two like fractions:
63/120 + 900/120 = 63 + 900/120 = 963/120
963/120 simplified gives 321/40
So, 21/40 + 45/6 = 321/40
In mixed form: 81/40

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