Add 12/10 and 42/80, Solve 1 2/10 + 42/80 as a fraction

Add 12/10 and 42/80

1^st number: 1 2/10, 2^nd number: 42/80

12/10 + 42/80 is 69/40.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 80 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 10 × 8 = 80,
12/10 = 12 × 8/10 × 8 = 96/80
Likewise, for the 2nd fraction, since 80 × 1 = 80,
42/80 = 42 × 1/80 × 1 = 42/80
Add the two like fractions:
96/80 + 42/80 = 96 + 42/80 = 138/80
138/80 simplified gives 69/40
So, 12/10 + 42/80 = 69/40
In mixed form: 129/40

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