Add 54/81 and 90/70, Solve 54/81 + 1 20/70 as a fraction

Add 54/81 and 90/70

1^st number: 54/81, 2^nd number: 1 20/70

54/81 + 90/70 is 41/21.

Find the least common denominator or LCM of the two denominators:
LCM of 81 and 70 is 5670

Next, find the equivalent fraction of both fractional numbers with denominator 5670
For the 1st fraction, since 81 × 70 = 5670,
54/81 = 54 × 70/81 × 70 = 3780/5670
Likewise, for the 2nd fraction, since 70 × 81 = 5670,
90/70 = 90 × 81/70 × 81 = 7290/5670
Add the two like fractions:
3780/5670 + 7290/5670 = 3780 + 7290/5670 = 11070/5670
11070/5670 simplified gives 41/21
So, 54/81 + 90/70 = 41/21
In mixed form: 120/21

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