Add 2/21 and 42/40, Solve 2/21 + 1 2/40 as a fraction

Add 2/21 and 42/40

1^st number: 2/21, 2^nd number: 1 2/40

2/21 + 42/40 is 481/420.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
2/21 = 2 × 40/21 × 40 = 80/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840
Add the two like fractions:
80/840 + 882/840 = 80 + 882/840 = 962/840
962/840 simplified gives 481/420
So, 2/21 + 42/40 = 481/420
In mixed form: 161/420

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