Add 21/42 and 90/30
1st number: 21/42, 2nd number: 3 0/30
21/42 + 90/30 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
21/42 = 21 × 5/42 × 5 = 105/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Add the two like fractions:
105/210 + 630/210 = 105 + 630/210 = 735/210 - 735/210 simplified gives 7/2
- So, 21/42 + 90/30 = 7/2
In mixed form: 31/2
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