Question

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Question 77, 78 and 79.

Answer 1

hi here you go ......

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I) in the first question 77........

the possible outcomes are : 10, 11, 12, 13........, 90
total possible outcomes = 81
total outcomes = 90

probability = 81/90 = 9/10 (ans)

II) here in this second question no 78.

total balls or total outcomes = 5+8= 13

total outcomes that it will be red = 5

probability = 5/13

III) here in question no 79.

total possible outcomes
={(6,6),, (6,1),, (6,2),, (6,3),, (6,4),, (6,5),, (1,6),, (2,6),, (3,6),, (4,6),, (5,6),, (6,6) }
=> total = 12

total outcomes = 36

probability = 12/36= 1/3...

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hope helped you :))

SWEATA SAHA :))

Answer 2

hey!!

here is your answer...

77) Probablity of getting two-digit numbers between 1 and 90..

we have to see on how many two-digit numbers are there between 1 and 90. till 9 it is one-digit, after 9 it is two-digit, starting from 10.

so, the total numbers are 90-9

which is 81, (total number of possibilities) , the total numbers are 90, so the Probablity would be 81/90.. :-)

78) there are 5 red and 8 green balls. Probablity of getting a red ball. Inorder to not get a red ball, we will have to take out any green ball and the number of green balls are 8 and the total number of outcomes is 8+5 which is 13, hence the possibility is 8/13 :-).


79) The total number of outcomes would be 36 as there are 6 possibilities on one dice, as it is thrown twice, the outcomes would be squared, which is 6^2 , 36.

sample space:- outcomes of not getting a six,

(1,6) (2,6) (3,6) (4,6) (5,6) (6,6) and, (6,1) (6,2) (6,3) (6,4) (6,5) (6,6) the total possibilities are, 12..

hence, possibility would be 12/36. :-)

general formula for possibility is

the total number of possibilities/ the total outcomes.

hope this helps!