Add 10/21 and 42/80
10/21 + 42/80 is 841/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
10/21 = 10 × 80/21 × 80 = 800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680 - Add the two like fractions:
800/1680 + 882/1680 = 800 + 882/1680 = 1682/1680 - 1682/1680 simplified gives 841/840
- So, 10/21 + 42/80 = 841/840
In mixed form: 11/840
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