Add 30/90 and 21/40
30/90 + 21/40 is 103/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 90 × 4 = 360,
30/90 = 30 × 4/90 × 4 = 120/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
120/360 + 189/360 = 120 + 189/360 = 309/360 - 309/360 simplified gives 103/120
- So, 30/90 + 21/40 = 103/120
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