Given number is 800.
One half of 800 is = [tex] \frac{1}{2} * 800 = \frac{800}{2} = 400 [/tex]
One tenth of one half of 800 is = [tex] \frac{1}{10} * 400 = \frac{400}{10} = 40 [/tex]
For finding one quarter of any number we divide it from 4.
So one quarter of one tenth of one half of 800 is = [tex] \frac{40}{4} = 10 [/tex]
So the answer is 10.