Add 42/21 and 30/80
1st number: 2 0/21, 2nd number: 30/80
42/21 + 30/80 is 19/8.
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,
42/21 = 42 × 80/21 × 80 = 3360/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
30/80 = 30 × 21/80 × 21 = 630/1680 - Add the two like fractions:
3360/1680 + 630/1680 = 3360 + 630/1680 = 3990/1680 - 3990/1680 simplified gives 19/8
- So, 42/21 + 30/80 = 19/8
In mixed form: 23/8
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