The given bar graph represents the pass percentage of 10th and 12th classes of a school during the consecutive four year period 2016-2019.

What is the average of percentage of the failed students of the 12th class for all four years?

23.75%

Fail percentage in 12th class in 2016 = 100 - 71 = 29

Fail percentage in 12th class in 2017 = 100 - 82 = 18

Fail percentage in 12th class in 2018 = 100 - 66 =  34

Fail percentage in 12th class in 2019 = 100 - 86  = 14

Average of percentage of the failed students of the 12th class

= \(\frac{29 + 18 + 34 + 14  }{4}\)

= \(\frac{ 95 }{4}\)

= 23.75%