Add 15/40 and 80/42, Solve 15/40 + 1 38/42 as a fraction

Add 15/40 and 80/42

1^st number: 15/40, 2^nd number: 1 38/42

15/40 + 80/42 is 383/168.

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,
15/40 = 15 × 21/40 × 21 = 315/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
80/42 = 80 × 20/42 × 20 = 1600/840
Add the two like fractions:
315/840 + 1600/840 = 315 + 1600/840 = 1915/840
1915/840 simplified gives 383/168
So, 15/40 + 80/42 = 383/168
In mixed form: 247/168

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