Add 7/42 and 81/20, Solve 7/42 + 4 1/20 as a fraction

Add 7/42 and 81/20

1^st number: 7/42, 2^nd number: 4 1/20

7/42 + 81/20 is 253/60.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
7/42 = 7 × 10/42 × 10 = 70/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
81/20 = 81 × 21/20 × 21 = 1701/420
Add the two like fractions:
70/420 + 1701/420 = 70 + 1701/420 = 1771/420
1771/420 simplified gives 253/60
So, 7/42 + 81/20 = 253/60
In mixed form: 413/60

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