Add 90/70 and 81/18, Solve 1 20/70 + 4 9/18 as a fraction

Add 90/70 and 81/18

1^st number: 1 20/70, 2^nd number: 4 9/18

90/70 + 81/18 is 81/14.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 18 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 70 × 9 = 630,
90/70 = 90 × 9/70 × 9 = 810/630
Likewise, for the 2nd fraction, since 18 × 35 = 630,
81/18 = 81 × 35/18 × 35 = 2835/630
Add the two like fractions:
810/630 + 2835/630 = 810 + 2835/630 = 3645/630
3645/630 simplified gives 81/14
So, 90/70 + 81/18 = 81/14
In mixed form: 511/14

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