It has no precision, since there is no following number.
The one farthest to the right of the decimal point (3).
To round a number to a particular digit, look at the digit immediately to the right of your target, in this case, the one pound place. If that digit is 4 or lower, zero it and everything to the right of it out. If that digit is 5 or higher, increase the target digit by one and zero everything to the right of it out. If your target digit is a 9, increasing it will turn it to zero and increase the digit to the left of it by one.
Only one . . . 999 .
The first digit can be any one of 9. (any digit except zero)For each of these . . .The second digit can be any one of 9. (any digit except whatever the first one is)For each of these . . .The third digit can be any one of 8. (any digit except whatever the first 2 are)Total possibilities = 9 x 9 x 8 = 648
In this case with 234.896 the last digit, '6' determines the precision since in is the last non-zero digit.
It has no precision, since there is no following number.
4
3
The last digit, 2.
7
7
8
3
If a number is given to the true degree of precision, this is always determined by its last digit - in this case, 6.
Always the last number, so in this example the precision is to hundredths.
The last digit, 6, determines its precision. 234.896 is presumed to be accurate to the nearest thousandth. If any other digit defined its precision, it would be pointless to write the others. For example, if we were told that 234.896 is only precise to the tens digit, it would suffice to write 230 because any additional digits would be meaningless.