Question 45706
A box contains 5 red and 7 green balls. How many ways can two balls be selected with the two balls the same color. Ok I gave this one my best shot..and I came up with 35, is this right. Thanks for checking.
TOTAL=12 BALLS...2 TO BE SELECTED

FOR 2 BALLS TO BE SAME COLOUR THEY COULD BE BOTH RED OR BOTH GREEN
COMBINATIONS WITH BOTH RED= 5C2=5*4/2=10
COMBINATIONS WITH BOTH GREEN =7C2=7*6/2=21
TOTAL =5C2+7C2=10+21=31