Add 90/21 and 54/18, Solve 4 6/21 + 3 0/18 as a fraction

Add 90/21 and 54/18

1^st number: 4 6/21, 2^nd number: 3 0/18

90/21 + 54/18 is 51/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126
Likewise, for the 2nd fraction, since 18 × 7 = 126,
54/18 = 54 × 7/18 × 7 = 378/126
Add the two like fractions:
540/126 + 378/126 = 540 + 378/126 = 918/126
918/126 simplified gives 51/7
So, 90/21 + 54/18 = 51/7
In mixed form: 72/7

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