The other tutor's solution is incorrect. He must have mistook
250 for 2500.
Later: He came back and fixed it!
250 is not a perfect square but it can be broken up into a perfect square
times a non-perfect square, for it can be broken up into 25*10, where 25
is a perfect square and 10 is a non-perfect square. so write 250 as 25*10.
is not a perfect square but it can be broken up into a perfect square
times a non-perfect square, for it can be broken up into 
, where 
is a perfect square and 
is a non-perfect square. so write as .
is not a perfect square but it can be broken up into a perfect square
times a non-perfect square, for it can be broken up into 
, where 
is a perfect square and 
is a non-perfect square. so write as .
Notice that I've colored all the perfect squares red. We can take their square
roots.
The square root of 25 is 5, so we can take out the 25 as a 5 in front of
the radical.
The square root of is 
, so we can take out the as
an in front of the radical.
Finally the square root of is , so we can take out the as just
in front of the radical.
.
Edwin
