To find place of a digit.
A) If the digit is before decimal: The digit just before decimal has unit place, the digit before that has tenths(10th) place, before that has 100th place and so on. If a number has no decimal, then assume that there is a decimal at the end.
Example: 153
Place of 3 = unit (1)
Place of 5 = 10th
Place of 1 = 100th
B) If the digit is after decimal: The digit just after decimal has place 1/10, after that 1/100 and so on.
To find value, multiply the digit by its place.
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Now let me answer your questions:
1) 5.812
The place of 8 = 1/10 (can also say tenths)
The value of 8 = 8 x 1/10 = 0.8
2) 66.492
The place of 2 = 1/1000 (can also say thousandths)
The value of 2 = 2 x 1/1000 = 0.002
Note: As you may have noticed, the value of a digit can also be found by replacing all digits except that digit in the number by 0.
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