What was the approximate percentage increase in the number of students of Engineering from year 2008 to 2009?

In 2008, number of students in Engineering = Total Student x 18%
In 2008, the number of students in Engineering = 35000x18/100 = 6300
In 2009, number of students in Engineering = Total Student x 19%
In 2009, the number of student in Engineering =40000 x19/100 = 7600
Required percentage = (number of students in Engineering in 2009 - number of students in Engineering 2008) x 100 / number of students in Engineering in 2008
Required percentage = (7600 - 3600)x 100 /6300 = 1300/63 = 20.6 ≈ 20%