00:01
In this question, we are asked to find the old numbers between 1 and 300, which are divisible either by 5 or by 6.
00:09
First of all, the number is divisible by 5 means that the number can be written in the form n equals to 5k, right? where k starts at 1, for k equals 1, we are going to get 5 right.
00:28
Then it becomes 2, 3 and so on, and the last value of k should correspond to 300.
00:35
And 5k equals to 300 means that k equals to 60.
00:42
So there are 60 numbers divisible by 5.
00:46
Now let's choose all the numbers divisible by 6.
00:50
A number is divisible by 6.
00:52
If we're going to write it in the form, m equals to 6l, right? l starts from 1 and goes all the way up to 50, right? because 6 times 50 equals to 300.
01:06
Now we need to, so there are how many 60 numbers divisible by 5, there are 50 numbers divisible by 6.
01:17
Now out of the 50 numbers divisible by 6, we want to remove those which are divisible also divisible by 5.
01:25
So we don't want to include the numbers divisible by 5.
01:31
And 6l is divisible by 5 implies that l is divisible by 5...