Add 30/80 and 70/40, Solve 30/80 + 1 30/40 as a fraction

Add 30/80 and 70/40

1^st number: 30/80, 2^nd number: 1 30/40

30/80 + 70/40 is 17/8.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 40 is 80

Next, find the equivalent fraction of both fractional numbers with denominator 80
For the 1st fraction, since 80 × 1 = 80,
30/80 = 30 × 1/80 × 1 = 30/80
Likewise, for the 2nd fraction, since 40 × 2 = 80,
70/40 = 70 × 2/40 × 2 = 140/80
Add the two like fractions:
30/80 + 140/80 = 30 + 140/80 = 170/80
170/80 simplified gives 17/8
So, 30/80 + 70/40 = 17/8
In mixed form: 21/8

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