So remember that dividing by a number is the same as multiplying by its reciprocal. To find a number's reciprocal, flip the numerator and the denominator around. In this case, 2/5 's reciprocal is 5/2.
With this information, flip 2/5 to its reciprocal, change the sign to multiplication, and multiply as such:
*Additionally, remember that 5 = 5/1
Your final answer is 25/2, which can be rewritten as 12 1/2 or 12.5.