Answer:
752
Step-by-step explanation:
For the number to be rounded off to 800, it needs to be either 750 or above or 850 and below.
With the given numbers, we can only have the following combinations:
257 ~ 300
275 ~ 300
527 ~ 500
572 ~ 600
725 ~ 700
752 ~ 800
And hence, 752 is the only combination of numbers that fits.
Hope this helps!