1/8
do tell if the ans is correct.
i ll post the soln there after
regards
rock
3/8 is the answer 😞
3/8 is the answer 😞
Hi All,
Another problem which I got stuck with :
0
* *
* * *
* * * *
* * * * *
1 2 | 3 4
The figure shown represents a board with 4 rows of pegs and at teh bottom of the board are 4 cells numbered 1 to 4. Whenever a ball (shown with 0) passes thru the opening between two adjacent pegs in the same row, it will hit the peg directly beneath the opening. The ball then has probablity 1/2 of passing thru the opening immediately to the left of that peg and probability of 1/2 of passing thru the opening immediately to the right. What is the probability that when the ball passes thru the first two pegs at the top, it will end up in cell 2.
1. 1/16
2. 1/8
3. 1/4
4. 3/8
5. 1/2
Approach and solution please....
Thanks is advance.
answer is 3/8
see the attached diagram...there are 3 possible ways in which the ball can reach 2 and each way has a probability of 1/2*1/2*1/2 = 1/8
hence, 1/8+1/8+1/8 = 3/8
can we have some
thnx more questions coming....
How many keystrokes are needed to type numbers from 1 to 1000?
A. 3001
B. 2893
C. 2704
D. 2890
E. None of these
How many keystrokes are needed to type numbers from 1 to 1000?
A. 3001
B. 2893
C. 2704
D. 2890
E. None of these
1 to 9 = 9
10 to 99 = 2*90 = 180
100 to 999 = 900 * 3 = 2700
1000 = 4
2700 + 180 + 9 + 4 = 2893
let me know if i've gone wrong somewhere.
slam.
1 to 9 = 9
10 to 99 = 2*90 = 180
100 to 999 = 900 * 3 = 2700
1000 = 4
2700 + 180 + 9 + 4 = 2893
let me know if i've gone wrong somewhere.
slam.
bang on target dude!!
The correct choice is (B)
here is the explanation
While typing numbers from 1 to 1000, you have 9 single digit numbers from 1 to 9. Each of them require one keystroke. That is 9 key strokes.
There are 90 two-digit numbers, from 10 to 99. Each of these numbers require 2 keystrokes. Therefore, one requires 180 keystrokes to type the 2 digit numbers.
There are 900 three-digit numbers, from 100 to 999. Each of these numbers require 3 keystrokes. Therefore, one requires 2700 keystrokes to type these 3 digit numbers.
Then 1000 is a four-digit number which requires 4 keystrokes.
Totally, therefore, one requires 9 + 180 + 2700 + 4 = 2893 keystrokes.
next question
In a class of 120 students numbered 1 to 120, all even numbered students opt for Physics, whose numbers are divisible by 5 opt for Chemistry and those whose numbers are divisible by 7 opt for Math. How many opt for none of the three subjects?
next question
In a class of 120 students numbered 1 to 120, all even numbered students opt for Physics, whose numbers are divisible by 5 opt for Chemistry and those whose numbers are divisible by 7 opt for Math. How many opt for none of the three subjects?
Hi There,
Can you please post the options with this q?
It would be helpful
Thanks,
Kartik
here it is with the options
In a class of 120 students numbered 1 to 120, all even numbered students opt for Physics, whose numbers are divisible by 5 opt for Chemistry and those whose numbers are divisible by 7 opt for Math. How many opt for none of the three subjects?
A. 19
B. 41
C. 21
D. 57
E. 26
here it is with the options
In a class of 120 students numbered 1 to 120, all even numbered students opt for Physics, whose numbers are divisible by 5 opt for Chemistry and those whose numbers are divisible by 7 opt for Math. How many opt for none of the three subjects?
A. 19
B. 41
C. 21
D. 57
E. 26
Hi There,
Thanks for the options.
I think the answer is E.26...
Regards,
Kartik
here it is with the options
In a class of 120 students numbered 1 to 120, all even numbered students opt for Physics, whose numbers are divisible by 5 opt for Chemistry and those whose numbers are divisible by 7 opt for Math. How many opt for none of the three subjects?
A. 19
B. 41
C. 21
D. 57
E. 26
lets look at the numbers from 1 to 120
divisible by 2 : 60 numbers
divisible by 5 : 24 numbers
divisible by 7 : 17 numbers
divisible by 10 : 12 numbers
divisible by 14 : 8 numbers
divisible by 35 : 3 numbers
divisible by 70 : 1 number
total = ( 60 + 24 + 17 ) - 12 - 8 - 3 + 1
= 102 - 23
= 79
so the answer here would be : 120 - 79 = 41
@kartik : you've arrived at 26, could you explain how?
@carobee : thank you for the question, looking forward to more.
people, please correct me if i'm wrong.
slam.
here it is with the options
In a class of 120 students numbered 1 to 120, all even numbered students opt for Physics, whose numbers are divisible by 5 opt for Chemistry and those whose numbers are divisible by 7 opt for Math. How many opt for none of the three subjects?
A. 19
B. 41
C. 21
D. 57
E. 26
the correct option is B). here is the detail explanation
We need to find out the number of students who took at least one of the three subjects and subtract that number from the overall 120 to get the number of students who did not opt for any of the three subjects.
Number of students who took at least one of the three subjects can be found by finding out A U B U C, where A is the set of those who took Physics, B the set of those who took Chemistry and C the set of those who opted for Math.
Now, AUBUC = A + B + C - (A n B + B n C + C n A) + (A n B n C)
A is the set of those who opted for Physics = 120/2 = 60 students
B is the set of those who opted for Chemistry = 120/5 = 24
C is the set of those who opted for Math = 120/7 = 17.
The 10th, 20th, 30th numbered students would have opted for both Physics and Chemistry.
Therefore, A n B = 120/10 = 12
The 14th, 28th, 42nd. Numbered students would have opted for Physics and Math.
Therefore, C n A = 120/14 = 8
The 35th, 70th . Numbered students would have opted for Chemistry and Math.
Therefore, A n B = 120/35 = 3
And the 70th numbered student would have opted for all three subjects.
Therefore, AUBUC = 60 + 24 + 17 - (12 + 8 + 3) + 1 = 79.
Number of students who opted for none of the three subjects = 120 - 79 = 41.
lets look at the numbers from 1 to 120
divisible by 2 : 60 numbers
divisible by 5 : 24 numbers
divisible by 7 : 17 numbers
divisible by 10 : 12 numbers
divisible by 14 : 8 numbers
divisible by 35 : 3 numbers
divisible by 70 : 1 number
total = ( 60 + 24 + 17 ) - 12 - 8 - 3 + 1
= 102 - 23
= 79
so the answer here would be : 120 - 79 = 41
@kartik : you've arrived at 26, could you explain how?
@carobee : thank you for the question, looking forward to more.
people, please correct me if i'm wrong.
slam.
Hi There,
Thanks for providing the rite ans along with proper explanation.
I did a mistake in the below step:
102-8=94...I dint include the LCM of 2,5 and 5,7..
so this comes to 120-94=26..
Thanks Again.
guys next question:
The owner of a hobby store needed to calculate the percentage of customers who purchase wood glue. Upon completing his survey, he noticed that 60% of the people that entered his store purchased an item. Of those customers, 15 percent purchased wood glue. What percent of the people that entered the store purchased wood glue?
a) 8
b) 7
c) 9
d) 12
e) 15
guys next question:
The owner of a hobby store needed to calculate the percentage of customers who purchase wood glue. Upon completing his survey, he noticed that 60% of the people that entered his store purchased an item. Of those customers, 15 percent purchased wood glue. What percent of the people that entered the store purchased wood glue?
a) 8
b) 7
c) 9
d) 12
e) 15
c) 9 basically (Assuming 100 people enter, 60 end up buying.So 15
percent of that 9 buy wood glue)
hi all,
let us assume that 100 ppl enter the store; of these 60% i.e. 60 ppl buy an item; of these 60 ppl 15%of 60 i.e. 9 ppl buy wood glue...
so %age of tht entered the store and purchased the wood glue is= this comes out to be 9 %...so my answer is C
any mistakes p[ls lemme know..
Regrds
Jakhar
guys next question:
The owner of a hobby store needed to calculate the percentage of customers who purchase wood glue. Upon completing his survey, he noticed that 60% of the people that entered his store purchased an item. Of those customers, 15 percent purchased wood glue. What percent of the people that entered the store purchased wood glue?
a) 8
b) 7
c) 9
d) 12
e) 15
guys next question:
The owner of a hobby store needed to calculate the percentage of customers who purchase wood glue. Upon completing his survey, he noticed that 60% of the people that entered his store purchased an item. Of those customers, 15 percent purchased wood glue. What percent of the people that entered the store purchased wood glue?
a) 8
b) 7
c) 9
d) 12
e) 15
c) is the correct answer. ur r all correct !!!!!! i guess the problem is simple and everyone has given the explanation, so this time i will refrain from giving one. shall i go to the next question?
@carobee,
sure thing ....go ahead..
regards
Jakhar
carobee Saysc) is the correct answer. ur r all correct !!!!!! i guess the problem is simple and everyone has given the explanation, so this time i will refrain from giving one. shall i go to the next question?
The sum of 5 consecutive integers is 35. How many of the five consecutive integers are prime numbers?
a) 0
b) 1
c) 2
d) 3
e) 4
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