( 120-80)÷80=50%

2. Find out their respective probabilities first.

( 1) 1/240

(2) 65438×40+0 in 6+0 is 65438 = 65438 in 240+0.

(3) The probability of choosing a boy: (240+20) ÷ 2 ÷ 240 = 13 out of 24.

2413x1301= one in 240th.

So it's also possible.