if a number is choosen between 100 and 999 includeing these
numberrs what is the provbabilty that the number selected
does not contain a 7 is
Answers were Sorted based on User's Feedback
Answer / jamesk
p = prob(1st digit not 7)*prob(2nd digit not 7)*prob(3rd
digit not 7)
=(8/9)*(9/10)*(9/10)
=0.72
Sandhya had it right except that there are 900 numbers
between 100 and 999 inclusive (not 899).
Is This Answer Correct ? | 59 Yes | 6 No |
Answer / seiko
no 0f 7's in 100 to 200 is
107,117,127,137,147,157,167,170,171,172,173,174,175,176,177,
178,179,187,197.
so total of 19 numbers between 100 and 199
repeat that for 200-299, 300-399,...,600-699, 800-899, 900-
999, we have 19*8 = 152 occurences
for 700-799, all 100 of them contain a 7
so total numbers contain a 7 is 152 + 100 = 252
total numbers between 100 and 999 is 900
probability = (900-252)/900 = 0.72
Is This Answer Correct ? | 51 Yes | 8 No |
Answer / ajeet
100-199------19
similarly for all ranges till 999 except for:
700-799----100
total no.containing 7's= 19*8+100=252
Therefore,
probability=(900-252)/900
= 648/900
= 0.72
Is This Answer Correct ? | 10 Yes | 3 No |
Answer / mayank kumar
total numbers between 100 and 999 =900
number that have a digit 7 between 100 and 199 =19
similarly no. that have digit 7 between 200 and 699=5*19
number that have digit 7 between 700 and 799=100
number that have a digit 7 between 800 and 999 =2*19
so total number that have digit seven in them between 100 and 999 are=8*19+100 =252
so numbers that does not have 7 digit in them =900-252 =648
therefore required prob, p =648/900 = 0.72
Is This Answer Correct ? | 6 Yes | 3 No |
Answer / shruti
here are 900 numbers between 100 and 999.
those that contain 7 are.....
107, 117, 127, ........ -- 10 of these
207, 217, 227, ........ -- 10 of these too
307, 317, 327, .......
....
9*10 numbers that end in 7.
170, 171, 172, 173, 174, 175, 176, (NOT 177 WE ALREADY COUNTED IT), 178, 179 -- 9 of these
270, 271, 272, 273, 274, 275, 276, (NOT 277 WE ALREADY COUNTED IT), 278, 279 -- 9 of these
...
and so on
so 9*9 numbers that have a middle digit of 7
and finally
700, 701, 702, 703, 704.................., but NOT
(707, 717, 727,....) or (770, 771, 772, 773, ....)
So that's (100 - 10 - 9) = 81 numbers that start with 7.
We had 900 numbers.
N = 900 - 90 - 81 - 81 = 648
So the probability is 648/900 = 0.72
Is This Answer Correct ? | 5 Yes | 3 No |
how to prepare for karnataka bank po exam? what'll be the topics in the exam?
1 Answers Bhel, Karnataka Bank,
4 times a number is twice the sum of the number and 5
Raghav marks his product 25% above the cost and then gives a discount of 20%.If the original price is Rs,25000 What is the final price?
A shopkeeper bought a watch for Rs.400 and sold it for Rs.500.What is his profit percentage?
A is sister of B. C is brother of D. D is sister of A. How is B related to D? (a) Brother (b) Brother or Sister (c) Sister (d) Data inadequate (e) None of these
please send the sample question of state bank of india to email id please.......that is quatitative aptitude,general awareness&resoning ability,marketing aptitude/computerknowledge,english,psycometry
2 Answers State Bank Of India SBI,
1 liter is evaporated from 6 liters, and liquid contain 4% of sugar. find % of sugar?
Subbu starts from a point O at 10.00 am , overtakes Ajay, who is moving in the same direction, at 11.00 a.m. and Bhuvan moving in the opposite direction at 12.00 (noon). If the speed of Bhuvan is one fourth the speed of Subbu, at what time will Ajay and Bhuvan cross each other.
3. A chicken farmer surveyed his flock with the following results. The farmer Has: 9 fat red roosters(male), 37 fat chickens 6 thin red roosters 2 fat red hens , 7 thin brown hens ,5 thin red hens 26 fat roosters (total) ,18 thin brown roosters Answer the following questions about the flock(HINT: in your Venn diagram make a circle for fat, for male and for red). How many chickens are: a) fat? __________ b) red? ___________ c) male? _________ d) fat, but not male? _________ e) brown, but not fat? ________ e) read and fat? _________
An important harbor city in the 14th century, it was repositioned in an effort to maintain its viability, a viability that remains to this day.
How do u write 6th may 2011 in 5 letters without using number??
On Monday a manufacturer processed a batch of bats, on Tuesday he processed three times as many, and on Wednesday he processed 4000 bats. In the three days, He processed 16000 bats. How many did he process on Tuesday?