Add 9/42 and 42/40, Solve 9/42 + 1 2/40 as a fraction

Add 9/42 and 42/40

1^st number: 9/42, 2^nd number: 1 2/40

9/42 + 42/40 is 177/140.

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

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 42 × 20 = 840,
9/42 = 9 × 20/42 × 20 = 180/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840
Add the two like fractions:
180/840 + 882/840 = 180 + 882/840 = 1062/840
1062/840 simplified gives 177/140
So, 9/42 + 42/40 = 177/140
In mixed form: 137/140

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