TCS
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Numerical Ability
Probability
Raj tossed three dice and their results are noted down. Find the total number of ways in which Raj can get the sum as 13. Also find the probability of get the sum as 10.
Read Solution (Total 6)
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- (6,6,1)=3!/2!=3
(6,5,2)=3!=6
(6,4,3)=3!=6
(5,5,3)=3!/2=3
(5,4,4)=3!/2!=3
total=21
P(sum 13)=21/216 - 11 years agoHelpfull: Yes(42) No(2)
- Always remember when 3 dice are rolled the number of ways of getting n ( where n is the sum of faces on dice)
= (n−1)C2 where n = 3 to 8
= 25 where n = 9, 12
= 27 where n = 10, 11
= (20−n)C2 where n = 13 to 18
The required probability for sum 10 is = 27/6^3 = 27/216
For sum 13 (20-13)C2=7C2=21[ where n=13]
The required probability for sum 13 is = 21/6^3 = 21/216= 7/72
- 11 years agoHelpfull: Yes(33) No(4)
- number of ways in which 13 can appear on three dices
(6,6,1) = 3! / 2! = 3
(6,5,2) = 3! = 6
(6,4,3) = 3! = 6
(5,5,3) = 3! / 2! = 3
(5,4,4) = 3! / 2! = 3
(6,3,4) = 3! = 6
So the total number of ways in which 13 can appear will be 3+6+6+3+3+6 = 27 - 11 years agoHelpfull: Yes(7) No(23)
- no of ways of 13=21;
p(10)=27/216; - 11 years agoHelpfull: Yes(2) No(2)
- i think it shud be 21*3/216
- 11 years agoHelpfull: Yes(0) No(0)
- i think it is 18
- 10 years agoHelpfull: Yes(0) No(0)
TCS Other Question
29) If x^2 < 1/100 and x< 0 What is the tightest range in which x can lie?
After an election, the newly constituted Geocity planning office is exploring the use of hollow cylinders for water towers, and have built a model in their office. The model is hollow, open (on top) right circular cylinder (with negligibly thin walls ), as shown in the figure below. An intelligent bug is sitting at the point A in the figure on the outside of the cylinder, and a drop of honey is accidentally dropped at point B (diametrically opposite to the bug, but inside the cylinder, and at a different distance from the top) The bug crawls to the honey on the outside and the inside of the cylinder by the shortest path. If the circumference of the top of the cylinder is 78 cm, d=27 cm, and h=53 cm, then what is the distance (in cm) crawled by the bug before reaching the honey? The answer is rounded to he nearest integer