Box A contains a black and a blue pen. Box B contains a black and a red pen. If one pen is taken from each what is the probability of both pen being different colour
Answers
Answer:
Total Blue Pens: 4
Total Red Pens: 2
Total Black Pens: 3
Total Pens: 4+2+3=9
Probability of drawing 2 blue pens =
9
C
2
4
C
2
=
9×8
4×3
=
6
1
After this, the pens are not replaced, which reduces the number of pens in the pack to 7.
So, the probability of drawing 1 black pen from a pack of 7 pens would be
7
C
1
3
C
1
=
7
3
Probability of drawing 2 blue pens and 1 black pen =
6
1
×
7
3
=
14
1
.
Answer:
Total Blue Pens: 4
Total Red Pens: 2
Total Black Pens: 3
Total Pens: 4+2+3=9
Probability of drawing 2 blue pens =
9
C
2
4
C
2
=
9×8
4×3
=
6
1
After this, the pens are not replaced, which reduces the number of pens in the pack to 7.
So, the probability of drawing 1 black pen from a pack of 7 pens would be
7
C
1
3
C
1
=
7
3
Probability of drawing 2 blue pens and 1 black pen =
6
1
×
7
3
=
14
1
.