There are 11pens in a box.8 are to black and 3 are red. two pens are taken out. work outthe probability that two are the same color.

If both pens are the same color, it means that they are either black and black or red and red.If without replacement,pr. of first black and second black is

8/11 and 7/10.Also, the pr of the first red and sencond red pen= 3/11 and 2/10.

Therefore pr. of bb or rr

(8/11×7/10)+(3/11×2/10)

56/110+6/110 =31/50