The first significant digit is the 5, which is in the ten-thousandth's position.
The 5.
Any digit in a number which is to the right of the first digit which isn't a zero, including the first digit
first you look at the first number tell what that number is then you just find the first digit.
The first non-zero digit from the left.
They all have 1 as the first digit.
4. All numbers before the first digit don't count. All numbers after the first digit for decimals do count.all digits shown in scientific notation are significant.
Look for the first digit that is different. In this case, the first digit after the decimal point. The number that has the larger digit in this position, is larger. If the first digit is the same, compare the second digit with the second digit, the third digit with the third digit, and so forth, until you find a difference.
You keep the first digit, replace the remaining digits with zero, and check whether you need to round the first digit up or not.
Five. Count from the first nonzero digit to the last nonzero digit.
-1510
You have 9 options for the first position (all except zero); 9 options for the second position (any digit except the digit used for the first position; 8 options for the third position; 7 options for the fourth position; 6 options for the fifth position; and 5 options for the sixth position. Multiply everything together.
All digits between the first non-zero digit and the last non-zero digits are significant. Some would argue that trailing 0s are significant since they are an indication of the precision of the number.