Add 21/42 and 36/5, Solve 21/42 + 7 1/5 as a fraction

Add 21/42 and 36/5

1^st number: 21/42, 2^nd number: 7 1/5

21/42 + 36/5 is 77/10.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 5 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210
Likewise, for the 2nd fraction, since 5 × 42 = 210,
36/5 = 36 × 42/5 × 42 = 1512/210
Add the two like fractions:
105/210 + 1512/210 = 105 + 1512/210 = 1617/210
1617/210 simplified gives 77/10
So, 21/42 + 36/5 = 77/10
In mixed form: 77/10

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