Add 42/4 and 21/30, Solve 10 2/4 + 21/30 as a fraction

Add 42/4 and 21/30

1^st number: 10 2/4, 2^nd number: 21/30

42/4 + 21/30 is 56/5.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 30 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 4 × 15 = 60,
42/4 = 42 × 15/4 × 15 = 630/60
Likewise, for the 2nd fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60
Add the two like fractions:
630/60 + 42/60 = 630 + 42/60 = 672/60
672/60 simplified gives 56/5
So, 42/4 + 21/30 = 56/5
In mixed form: 111/5

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