Add 10/21 and 42/40
1st number: 10/21, 2nd number: 1 2/40
10/21 + 42/40 is 641/420.
Steps for adding fractions
- 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,
10/21 = 10 × 40/21 × 40 = 400/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
42/40 = 42 × 21/40 × 21 = 882/840 - Add the two like fractions:
400/840 + 882/840 = 400 + 882/840 = 1282/840 - 1282/840 simplified gives 641/420
- So, 10/21 + 42/40 = 641/420
In mixed form: 1221/420
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