Add 18/40 and 50/42, Solve 18/40 + 1 8/42 as a fraction

Add 18/40 and 50/42

1^st number: 18/40, 2^nd number: 1 8/42

18/40 + 50/42 is 689/420.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
50/42 = 50 × 20/42 × 20 = 1000/840
Add the two like fractions:
378/840 + 1000/840 = 378 + 1000/840 = 1378/840
1378/840 simplified gives 689/420
So, 18/40 + 50/42 = 689/420
In mixed form: 1269/420

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