Before you understand Descending Order of Decimals: You must know:
Place Value of Digit in Decimals ?
How to Compare Decimals ?
Arranging decimals in descending order means that arranging decimals in decreasing order i.e. we start with the largest decimals and then next 2nd largest decimal & so on; till we reach the smallest decimal which is written at the last place.
Follow the following steps for arranging decimals in descending order:
Step 1: We start with comparing the Whole Number Part of Decimals and decimal with the largest whole number part is to be written at first place in the order.
Step 2: Then we find a decimal whose whole number part is smaller than the whole number part of decimal selected earlier in step 1, but larger than whole number part of remaining decimals.
Step 3: And then we find a decimal whose whole number part is smaller than the whole number part of decimal selected earlier in step 2, but larger than whole number part of remaining decimals.
These Steps are repeated in similar ways till we are left with only one decimal, whose whole number part is the smallest among whole number parts of all the given decimals and it would be written at the last place of the order.
Example  Let’s try arranging the following series of decimals in descending order:
181.98, 64.78, 345.75, 9.72, 0.05, 1.8
Solution: This proceeds in the following steps:
Step 1: We start with comparing the Whole Number Part of Decimals and decimal with the largest whole number part is to be written at first place in the order, we get:
345 is the largest whole number part of decimal 345.75 from the given series, so it is written at the first place of descending order.
Descending Order = 345.75
Step 2: Then we find a decimal whose whole number part is smaller than the whole number part of decimal selected earlier in step 1, but larger than whole number part of remaining decimals and we get:
181 is the whole number part of decimal 181.98
And it is smaller than the 345, which is the whole number part of decimal 345.75, but larger than whole number part of remaining decimals.
So 181.98 is written next to decimals 345.75 in the descending order and we get series:
Descending Order Series = 345.75, 181.98
Step 3: Then we find a decimal whose whole number part is smaller than the whole number part of decimal selected earlier in step 2, but larger than whole number part of remaining decimals and we get:
64 is the whole number part of decimal 64.78
And it is smaller than the 181, which is the whole number part of decimal 18.98, but larger than whole number part of remaining decimals.
So 64.78 is written next to 181.98 in the descending order and we get series:
Descending Order Series = 345.75, 181.98, 64.78
Step 4: Then we find a decimal whose whole number part is smaller than the whole number part of decimal selected earlier in step 3, but larger than whole number part of remaining decimals and we get:
9 is the whole number part of decimal 9.72
And it is smaller than the 64, which is the whole number part of decimal 64.78, but larger than whole number part of remaining decimals.
So 9.72 is written next to 64.78 in the descending order and we get series:
Descending Order Series = 345.75, 181.98, 64.78, 9.72
Step 5: Then we find a decimal whose whole number part is smaller than the whole number part of decimal selected earlier in step 4, but larger than whole number part of remaining decimals and we get:
1 is the whole number part of decimal 1.8
And it is smaller than the 9, which is the whole number part of decimal 9.72, but larger than whole number part of remaining decimals.
So 1.8 is written next to 9.72 in the descending order and we get series:
Descending Order Series = 345.75, 181.98, 64.78, 9.72, 1.8
Step 6: Lastly, we are left with only one decimal, whose whole number part is the smallest among whole number parts of all the given decimals and it would be written in the last place of the order:
Since decimal 0.05, whose whole number part is 0 and the smallest among whole numbers part of all the given decimals, so 0.05 would be written at the last place of the descending order and we get complete series:
Descending Order Series = 345.75, 181.98, 64.78, 9.72, 1.8, 0.05

Study More Solved Questions / Examples
Arrange the following series in descending order:
0.72, 11.201, 0.68, 8.03, 3.007 
Arrange the following series in descending order:
3.35, 10.12, 10.55, 100.7, 10.8 
Arrange following decimals in descending order:
0.42, 0.27, 0.68, 0.15 
Arrange the following series in descending order:
7.234, 7.271, 7.222, 7.210 
