Three dices are thrown. If score is calculated as sum of

Question

Three dices are thrown. If score is calculated as sum of numbers that appear on all three dices, what is the probability of a score in a range 3-10 inclusive.

christoph · Answer

1/3 <img src="{SMILIES_PATH}/icon_question.gif" alt=":?:" title="Question" />

cool_jonny009 · Answer

7/8

all the result having 4 5 6 will have sum more than 10 

so total no of combination with 456 ( incuding the repeating each number) = 3*3*3=27

total no of possible out comes = 6*6*6=216

so P = 1 - 1/8= 7/8

what is OA ..?

bewakoof · Answer

When do we get sum > 10.. 
in cases
1st 2nd 3rd
6 6 ---> Hence if we get a 6 first then = 1/6, probability 
 of getting 6or 5 or 4 in the second draw is 3/6.
6 5 Therefore total probability = 1/6 *3/6.. Now 6 
 can come in first, second or third draw.
6 4

Similarly, for 5 6 and 55 will result in bad cases.. 1/6 *2/6 *3 

and in 46 can be a bad case .. 1/6 *1/6

Hence total = 1/6 *3/6 * 3 + 1/6 *2/6 *3 + 1/6 *1/6 = 1/2

1-1/2 = 1/2.

I wont be surprised if i went wrong somewhere

rianah100 · Answer

I would probably guess if this shows up in the real test:
Figuring out 3-10 inclusive as hard as the NOT case (11..18 inclusive). Seems like too many possibilities. Does anyone know of an easy way?

GMATT73 · Answer

My method (45 seconds)

Lowest possible total: 3 (1-1-1)
Highest possible total: 18 (6-6-6)

Difference, inclusive of 3 and 18 = 16

Probability= #desired outcomes/#total possible outcomes

Desired outcomes (3-10)= 8
Possible outcomes= 16

8/16---> 1/2

(unless a dice falls off the table and the cat gobbles it up before you can read it) 8-)

duttsit · Answer

bingo...you gottit..good job matt. bewakoof was close as well.

if we try a few steps we get a pattern that:
in this case(when three dices are thrown):

p(getting score n) = p(getting score (21-n))

for example:
p(getting score 3) = 1-1-1= 1/6*1/6*1/6
p (getting 10 - 3 = 18) = 6-6-6 = 1/6 * 1/6 * 1/6

so p(getting score 3-10) = p (score 11-18)

cool_jonny009 · Answer

oppss!!!! My answer is way off..

but can somebody tell me why the answer by this approach comes wrong..
....
Mats method is good ..but just to clear my concept here ...i wann know what is wrong in this approach....
'

amy_v · Answer

How do you account for numbers like 614 and 156? the bold sentence does not cover all options.

ywilfred · Answer

what he (or she) meant was each die rolled 4 and up. This is how he arrived at 3*3*3. If we used your example of 614, we won't get 3*3*3.

Three dices are thrown. If score is calculated as sum of

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