Cómo se hace esta operación?

PD: explica cómo se hace. gracias​

Abox contains 1 plain pencil and 4 pens. a second box contains 5 color pencils and 5 crayons. one item from each box is chosen at random. what is the probability that a plain pencil from the first box and a color pencil from the second box are selected? write your answer as a fraction in simplest form.

Need this asap if anyone can i would be very grateful. if you could show workings that would really

Rewrite the following quadratic functions in intercept or factored form. show your work. f(x) = 3x^2 - 12