Exercise · ZW-LEAST-COMMON-MULTIPLE-004 · ★★☆ Intermediate
If \( \gcd(a,b)=1 \), with \( a=14 \) and \( b=15 \), what is \( \operatorname{lcm}(a,b) \)?
Choose one option.
Show answer
- C. \( 210 \)
Explanation
Since \( \gcd(14,15)=1 \), the relation \( \operatorname{lcm}(a,b)\cdot\gcd(a,b)=|ab| \) gives \( \operatorname{lcm}(14,15)=14\cdot 15=210 \). The option with 29 adds the two numbers.
Review the concept: Least common multiple
The least common multiple of two integers a and b is the smallest positive integer that is a multiple of both, denoted \( \operatorname{lcm}(a,b) \).
\[\operatorname{lcm}(a,b)=\dfrac{|ab|}{\gcd(a,b)}\]
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