Total fish in lake = 10 + 23 + 39 = 72
Percentage perch 10/72 = 13.88% 13.88% of a complete circle pie chart
is .1388 x 360 degrees = 50 degrees
Bream 23/72 = 31.94% = 115 degrees
Carp 39/72 = 195 degrees on the pie chart
TOTAL should equal 360 degrees
as a checkkk 50 + 115 + 195 = 360 Check!
Now just draw out the pie chart with the sectors as above ......
It appears you have drawn in the 195 sector for carp.....now draw in the 50 and 115 sectors in the remaining space on the pie chart for perch and bream respectively.....