How about this one guys.... Kurt, a painter, has 9 jars of paint: 4 are yellow 2 are red rest are brown Kurt will combine 3 jars of paint into a new container to make a new color, which he will name accordingly to the following conditions: Brun Y if the paint contains 2 jars of brown paint and no yellow Brun X if the paint contains 3 jars of brown paint Jaune X if the paint contains at least 2 jars of yellow Jaune Y if the paint contains exactly 1 jar of yellow What is the probability that the new color will be Jaune a) 5/42 b) 37/42 c) 1/21 d) 4/9 e) 5/9 Thanks in advance.
TWO couples and a single person are to be seated on 5 chairs such that no couple is seated next to each other. What is the probability of the above??
Explanations please....
2/5 ? Probability that 2 couples are never together is complement of any of the couples are always together. P(any are together) = P(one couple is together) + P(the other one couple is together) - P(both couples are together) = (4! * 2) + (4! * 2) - (3! * 2 * 2) =4! * 3 Total permutations possible = 5! So answer = 1 - (4!*3/5!) = 2/5
Cud u pls explain the equation "4!*2 + 4!*2 - ...."
Thanks.
calculating that a couple is always together is similar to this question-
Calculate the number of arrangements of the letters of the word ABCDE if both the A and B are together ? Answer Duct-tape the A and B together. Then we have four "letters" to arrange: B, C, D, E, There are: 4! = 24 ways to arrange these four "letters". But the can be permuted in 2 Total permutations = 4!*2
But the no of yellow jars is 4. So P(JuaneX)=/ should be =(4C2.5C1+4C3)/(9C3) instead of =(3C2.6C1+3C3)/(9C3). and P(JuaneY)=/ should be =(4C1.5C2)/(9C3) instead of =(3C1.6C2)/(9C3)
Yes, the answer is B. Can u please explain. Thanks.
Total Jars = 9 4- Yellow- Y 2- Red- R 3- Brown- B Combining 3 Jars So Total probability is 9C3 (C Combination) 9! / 3!*6! 84 Probability that the new colour will be Juane (Jaune X if the paint contains at least 2 jars of yellow) + (Jaune Y if the paint contains exactly 1 jar of yellow) ( 2Y+1R or 2Y+1B or 3Y)+(1Y+2R or 1Y+2B or 1Y+1R+1B) 2Y+1R => 4C2 * 2C1 => 12 2Y+1B => 4C2 * 3C1 => 18 3Y => 4C3 => 4 1Y+2R => 4C1 * 2C2 => 4 1Y+2B => 4C1 * 3C2 => 12 1Y+1R+1B => 4C1 * 2C1 * 3C1 => 24 12+18+4+4+12+24 74 74/84 37/42
A merchant sells an item at a 20% discount, but still makes a gross profit of 20 percent of the cost. What percent of the cost would the gross profit on the item have been if it had been sold without the discount?
Tanya prepared 4 different letters to be sent to 4 different addresses. For each letter, she prepared an envelope with its correct address. If the 4 letters are to be put into the 4 envelopes at random, what is the probability that only 1 letter will be put into the envelope with its correct address?
A merchant sells an item at a 20% discount, but still makes a gross profit of 20 percent of the cost. What percent of the cost would the gross profit on the item have been if it had been sold without the discount?
A certain car averages 25 miles per gallon of gasoline when driven in the city and 40 miles per gallon when driven on the highway. According to these rates, which of the following is the closest to the number of miles per gallon that the car averages when it is driven 10 miles in the city and then 50 miles on the highway?
A certain portfolio consisted of 5 stocks, priced at $20, $35, $40, $45 and $70, respectively. On a given day, the price of one stock increased by 15%, while the price of another decreased by 35% and the prices of the remaining three remained constant. If the average price of a stock in the portfolio rose by approximately 2%, which of the following could be the prices of the shares that remained constant?
me an army officer...use to read ur post quite often..however replying to u now...
me trying my luck on 9th....not getting good accuracy in CR and RC.....suggest a few clicking tips other than those mentioned in the recommended books....
i have nearly 6yrs exp in army, basically from dbg
Q. How many 4-digit integers are there in which all 4 digits are even? A. 625 B. 600 C. 500 D. 400 E. 256
Help me puys!
Thousands digit can be filled with any of 2,4,6,8 -> 4 ways Hundreds digit can be filled with any of 0,2,4,6,8 -> 5 ways Tenth digit can be filled with any of 0,2,4,6,8 -> 5 ways Unit digit can be filled with any of 0,2,4,6,8 -> 5 ways
Thanks Ankit, for the explanation. The OA is indeed 1/3.
This is what I did though.. Can you plz tell me where I went wrong?
Assuming the letters are A,B,C,D and the boxes are 1,2,3,4 If we work them out, we'll find that there are 16 letter-box pairs possible. Out of these 16 pairs only 4 pairs have letters being put correctly into their respective boxes. So the probability that only 1 letter is put into the correct box is 4/16 = 1/4.
I wonder why these probability questions even turn up in the exam :-(
My pick would be D) 1/3...wats the OA?
Let the envelopes be named as A,B,C,D and letters be a,b,c,d
Total number of ways in which we can put 4 letters in 4 envelopes is 4!
Total number of ways in which we can have only one letter in its correct envelope:
Lets take the case of one particular letter going into right envelope and calculate the no of cases. Then, we can multiply that no wid 4 to get the total instances.
Let us suppose that A-a pair gets made.
Thus, total no of combinations possible here = 2.
Thats because A can be filled in 1 way (only by a) Then, B can be filled in 2 ways (by c or d) Then, C can be filled in 1 way( if u fill B with c, u cant fill C with b & if you fill B with d, u cant fill C with c) Then,D can be filled in 1 way only
Thus, fixing one pair, we get total 2 ways. Thus for 4 possible pairs, total ways are 8
prob=8/4! = 1/3
difficult explanation. I hope it helps and is correct at first place.
A certain car averages 25 miles per gallon of gasoline when driven in the city and 40 miles per gallon when driven on the highway. According to these rates, which of the following is the closest to the number of miles per gallon that the car averages when it is driven 10 miles in the city and then 50 miles on the highway?
