Add 15/10 and 54/42, Solve 1 5/10 + 1 12/42 as a fraction

Add 15/10 and 54/42

1^st number: 1 5/10, 2^nd number: 1 12/42

15/10 + 54/42 is 39/14.

Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 10 × 21 = 210,
15/10 = 15 × 21/10 × 21 = 315/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
54/42 = 54 × 5/42 × 5 = 270/210
Add the two like fractions:
315/210 + 270/210 = 315 + 270/210 = 585/210
585/210 simplified gives 39/14
So, 15/10 + 54/42 = 39/14
In mixed form: 211/14

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