Add 40/21 and 42/27, Solve 1 19/21 + 1 15/27 as a fraction

Add 40/21 and 42/27

1^st number: 1 19/21, 2^nd number: 1 15/27

40/21 + 42/27 is 218/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189

Next, find the equivalent fraction of both fractional numbers with denominator 189
For the 1st fraction, since 21 × 9 = 189,
40/21 = 40 × 9/21 × 9 = 360/189
Likewise, for the 2nd fraction, since 27 × 7 = 189,
42/27 = 42 × 7/27 × 7 = 294/189
Add the two like fractions:
360/189 + 294/189 = 360 + 294/189 = 654/189
654/189 simplified gives 218/63
So, 40/21 + 42/27 = 218/63
In mixed form: 329/63

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