Add 21/70 and 42/10, Solve 21/70 + 4 2/10 as a fraction

Add 21/70 and 42/10

1^st number: 21/70, 2^nd number: 4 2/10

21/70 + 42/10 is 9/2.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 10 is 70

Next, find the equivalent fraction of both fractional numbers with denominator 70
For the 1st fraction, since 70 × 1 = 70,
21/70 = 21 × 1/70 × 1 = 21/70
Likewise, for the 2nd fraction, since 10 × 7 = 70,
42/10 = 42 × 7/10 × 7 = 294/70
Add the two like fractions:
21/70 + 294/70 = 21 + 294/70 = 315/70
315/70 simplified gives 9/2
So, 21/70 + 42/10 = 9/2
In mixed form: 41/2

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