Add 21/14 and 6/90, Solve 1 7/14 + 6/90 as a fraction

Add 21/14 and 6/90

1^st number: 1 7/14, 2^nd number: 6/90

21/14 + 6/90 is 47/30.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 14 × 45 = 630,
21/14 = 21 × 45/14 × 45 = 945/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
6/90 = 6 × 7/90 × 7 = 42/630
Add the two like fractions:
945/630 + 42/630 = 945 + 42/630 = 987/630
987/630 simplified gives 47/30
So, 21/14 + 6/90 = 47/30
In mixed form: 117/30

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