 Hello and welcome to the session. In this session we discussed the following question which says round of 34.2106 correct to 4 significant digits. First of all we will define significant digits. These are the total number of digits present in a number except the zeroes preceding the first numeral. Now we have certain steps to round off the decimal number to the required number of significant digits. Let's see what are these steps that we need to follow. In the first step we retain the digits, the required number. In the next step we see the extra digit retained and if the extra digit retained to the digit just before it we leave the digit and in the last step the extra digit is then this is the key idea that we would follow to solve this question. Let's proceed with the solution now. Now the given decimal number is 34.2106 and we make to round this off on significant digits. The significant digits are the total number of digits which are present in a number except the zeroes preceding the first numeral. So we can see that in the given decimal number that is 34.106 the number of significant digits is 3, 4, 2, 1, 0 and 6. So there are total 6 significant digits in the given decimal number. Now since we need to round off this decimal number to 4 significant digits we would retain up to one more than the required number of significant digits and the required number of significant digits are 4. So one more than 4 would be 5. So we would retain 5 digits, we retain, we equal to 34.210. We see the extra digit that is retained, digit retained in sets again. If the extra digit is 5 or more than 5 then we would add 1 to the digit just before it. But in this case the extra digit that is 0 is less than 5 the digit just before it as such. The extra digit retained is 0 which is less than 5 the digit therefore we get the number as 34 point this number is correct for significant digits. We have rounded off the given decimal number that is 34.2106 to 34 point plus significant. This is our final answer. With this we complete the session. Hope you understood the solution of this question.