Add 81/70 and 15/4, Solve 1 11/70 + 3 3/4 as a fraction

Add 81/70 and 15/4

1^st number: 1 11/70, 2^nd number: 3 3/4

81/70 + 15/4 is 687/140.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 4 is 140

Next, find the equivalent fraction of both fractional numbers with denominator 140
For the 1st fraction, since 70 × 2 = 140,
81/70 = 81 × 2/70 × 2 = 162/140
Likewise, for the 2nd fraction, since 4 × 35 = 140,
15/4 = 15 × 35/4 × 35 = 525/140
Add the two like fractions:
162/140 + 525/140 = 162 + 525/140 = 687/140
So, 81/70 + 15/4 = 687/140
In mixed form: 4127/140

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