Add 15/40 and 80/70, Solve 15/40 + 1 10/70 as a fraction

Add 15/40 and 80/70

1^st number: 15/40, 2^nd number: 1 10/70

15/40 + 80/70 is 85/56.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 40 × 7 = 280,
15/40 = 15 × 7/40 × 7 = 105/280
Likewise, for the 2nd fraction, since 70 × 4 = 280,
80/70 = 80 × 4/70 × 4 = 320/280
Add the two like fractions:
105/280 + 320/280 = 105 + 320/280 = 425/280
425/280 simplified gives 85/56
So, 15/40 + 80/70 = 85/56
In mixed form: 129/56

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