The ratio between two numbers is 3:7 and their LCM is 210. The first number is
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 30
Numbers in the ratio 3 : 7 can be written as \(3k\) and \(7k\). Since 3 and 7 have no common factor, their LCM is \(3\times7\times k=21k\).
\(21k=210\), so \(k=10\)
The numbers are 30 and 70, so the first number is 30