Add 4/42 and 21/90
4/42 + 21/90 is 23/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
4/42 = 4 × 15/42 × 15 = 60/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Add the two like fractions:
60/630 + 147/630 = 60 + 147/630 = 207/630 - 207/630 simplified gives 23/70
- So, 4/42 + 21/90 = 23/70
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