Question

There are 4 boxes colored red, yellow, green and blue. If 2 boxes are selected, how many combinations are there for at least one green box or one red box to be selected?
a..1 b.. 6 c.. 9 d… 5

Answer 1

come on gys

Answer 2

c

Answer 3

wait wait

Answer 4

Its 5

Answer 5

my answer is 5

Answer 6

how u solve it

Answer 7

select green first..then there are 3 ways to select the second box..you get 3 ways if you select red box first..but there is one combination repeating in this process...(green,red) when green selected first and (red,green) when red selected first..since both the combinations are same..subtract 1 from the 6 ways..So, its 5

Answer 8

i solve it as 1 1R AND 1Y=1C1*1C1=1
1R AND 1B=1C1*1C1=1
1G AND 1IY=1C1*1C1=1
1G AND 1B=1C1*1C1=1
1G AND 1R=1C1*1C1=1
SO TOTAL IS 5
WT DO U THINK

Answer 9

Its correct and good with this problem as the numbers are small...but appears lengthy when the numbers are large..

Answer 10

OK U R RIGHT

Answer 11

Select...
1G in 1C1=1 way. The other box can be of any colour from the remaining three colours..So, you can select the second box in 3C1 = 3 ways...
Similarly, do it for red too..But here, the second box should not be green as the combination is already selected above..So, the second box can be selected in 2C1=2ways..
Total ways=5

Answer 12

THNX TO OPEN MY EYES

Answer 13

i was little bit wrong ,,

Answer 14

welcome : )