20e In a class of 45 students it is known that 24 of then do Ait, 20 do Chemistry and 22 do Biology. All students do af least one of the Bhree students. 3 do all è three subjects while 7 do Xrt \{ Biology. 6 do Xrt 5 chemistry, but not Bidogy. 8 do chamistry \$ Bidogy
How many do
a Biology onhy
chemitty only Art only
* Two subjects only
Solve