Nonzero digits

In the class, Greg said that 0.11111x0.33333 has 3 digits.
When I calculated it, there are 3,7,2,9,6.

What is the point that we need to here?
if we multiply with a certain number with 0.11111, it will be the same number of digits?
Then if we multiply 0.111111 with any number, the number of digits will be the same?

Thank you

I just did as well, the calculator said “0.0370363”, that is 3 non-zero distinct numbers: 3,6,7

No, not necessarily
0.11111 * 5 = 0.55555 = 1 digit
0.11111 * 22 = 0.0244442 = 2 digits
Can you share a link to the video in question?

I just did as well, the calculator said “0.0370363”, that is 3 non-zero distinct numbers: 3,6,7
→ sorry I meant 0.111111x0.333333. then there are more than 3 distinct numbers

The video is from 2 months plan, day3, quant practice. I stlil don’t get it :frowning: Greg said if we multiply something with 0.111111111, it will have the same number of digits like 0.1111111x0.625 will have 3. but if I multiply 0.1111 with 0.625, there are more than 3 digits… maybe there is a rule that 1 should be more than a certain number, like not 0.1111, it should be 0.111111?

I think what he meant there, is that whether you multiply a non-terminating (with same digit) rational number with 0.111 or 0.11111, you are going to get a pattern of the same digits
through pascal’s triangle, you can observe that

11 * 33 = 363
111 * 333 = 36963
1111 * 3333 = 369(1)2963 = 3702963
11111 * 33333 = 369(1)2(1)5(1)2963 = 370362963

In the exam however if such a question turns up, I would recommend simply checking the \frac{1}{3^2*4^2} in the calculator
to see how many repeating digits does it has

Here, in the recorded video greg said that multiply by 1 gives the same digit and selected the and three, but in the end it was 0.1111… * 0.0625 , so even if we ignore all the ones and keep only two 1s, the answer will have 6875 as non zero digits which changes the and to 4. So, is 3 the right answer by some assumption?

So, I actually used the calculator and possible answers were 3, 4, 5 and 6. And since, 3 is only available in the choice that makes it the answer.

If you actually go to the calculator and divide 1 by 4, then by 9 follower by 16 and 25
The answer you get is 0.0000694444
That is 3 digits - 6,9,and 4

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