Question

if HCF (a, b) =18 then LCM (a,b)=........... is not possible
a) 36
b)27
c) 72
d) 108​

Answer 1

Answer:

b) 27

Step-by-step explanation:

HCF is always a factor of LCM. But 27 isn't divisible by 18.

Answer 2

Answer:

LCM(a,b)=27 is not possible.

So option b is the correct answer.

Step-by-step explanation:

Here given two numbers are a and b.

And HCF of a and b is 18.

Now we need to find LCM.

We know, LCMxHCF= Product of two numbers

LCM=$\frac{Product \: of \: two \: numbers}{HCF}$

Here two numbers are a and b and HCF is 18.

So,LCM$= \frac{a \times b}{18}$

It is clear that LCM of a and b is divisible by 18.

By option testing rule we can solve this question,

For option a:

The number is 36.

36 is divisible by 18.So it is possible that 36 ia LCM of a and b.

So,36 is not our answer.

For option b:

The number is 27.

27 is not divisible by 18.So it is not possible that 27 is LCM of a and b.

So,27 is our answer.

For option c:

The number is 72.

It is also divisible by 18.

So it is clear that 72 is possible LCM of a and b.

For option d:

Here 108 is also divisible by 18.So it is possible that 108 is LCM of a and b.

So,108 is not our answer.

There LCM(a,b)=27 is not possible.