Form the greatest 5-digit odd number with the digits.Use each digit only once. 8, 1, 4, 5, 7

Sure, here are the steps to form the greatest 5-digit odd number using the digits 8, 1, 4, 5, 7:

1. To form the greatest number, the highest digit should be placed at the left-most side or the highest place value. In this case, the highest digit is 8. So, place 8 at the ten thousands place.

2. Next, place the next highest digit at the thousands place. The next highest digit is 7. So, place 7 at the thousands place.

3. Continue this pattern for the hundreds and tens place. The next highest digits are 5 and 4 respectively. So, place 5 at the hundreds place and 4 at the tens place.

4. However, since we need to form an odd number, the digit at the ones place should be odd. The only digit left is 1, which is an odd number. So, place 1 at the ones place.

So, the greatest 5-digit odd number that can be formed using the digits 8, 1, 4, 5, 7 is 87541.