Question 59267
x varies inversely as v

==> x = K/v for some constant K

given x = 45 when v = 2.

Plugging in these values in the above ,
45 = K/2
==>  K = 90

So x = 90/v

When v = 10, 

x = 90/v

  = 90/10
  = 9

So when v = 10, x = 9