Add 81/70 and 42/40, Solve 1 11/70 + 1 2/40 as a fraction

Add 81/70 and 42/40

1^st number: 1 11/70, 2^nd number: 1 2/40

81/70 + 42/40 is 309/140.

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

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 70 × 4 = 280,
81/70 = 81 × 4/70 × 4 = 324/280
Likewise, for the 2nd fraction, since 40 × 7 = 280,
42/40 = 42 × 7/40 × 7 = 294/280
Add the two like fractions:
324/280 + 294/280 = 324 + 294/280 = 618/280
618/280 simplified gives 309/140
So, 81/70 + 42/40 = 309/140
In mixed form: 229/140

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