Add 15/40 and 90/42, Solve 15/40 + 2 6/42 as a fraction

Add 15/40 and 90/42

1^st number: 15/40, 2^nd number: 2 6/42

15/40 + 90/42 is 141/56.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
90/42 = 90 × 20/42 × 20 = 1800/840
Add the two like fractions:
315/840 + 1800/840 = 315 + 1800/840 = 2115/840
2115/840 simplified gives 141/56
So, 15/40 + 90/42 = 141/56
In mixed form: 229/56

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