Campus Maths Puzzle Numerical Ability

A refrigerator contains 12 cans.7 blue cans and 5 red cans. In how many ways can we remove 8 cans from the refrigerator so that at least 1 blue can and red can remains in the refrigerator.

Read Solution (Total 1)

possible draw 8 balls and in refrigirator contains atleast 1 blue and 1 red ball are (6,2) (5,3) (4,4)
6 2---->7c6*5c2--->7*10=70
5 3---->7c5*5c3--->21*10=210
4 4---->7c4*5c4--->35*5=175

70+210+175=455
4 4---->
11 years agoHelpfull: Yes(0) No(1)

Campus Other Question

Tap A can fill the tank in 20 hours and tap B can fill in 10 hours. An outlet tap C at the bottom can empty the tank in 15 hours and another outlet tap D, at the middle, can empty it in 25 hours. At first, taps A and C were opened for 15 hours and then B and D were also opened. After how much time, from the beginning, would the tank be filled? Q. It is better to have 70% discount or 40 and 30% discount consequently?