Advertisements
Advertisements
प्रश्न
Four pipes A, B, C and D can fill a tank with water in 15, 20, 30 and 60 hours respectively. Pipe A is opened at 4 a.m., B at 5 a.m., C at 6 a.m. and D at 7 a.m. When is the tank filled up completely?
विकल्प
9:30 a.m.
10:00 a.m.
10:30 a.m.
11:00 a.m.
उत्तर
11:00 a.m.
Explanation:
Let the tank filled up after x hours when pipe A is opened
So, `"x"/15+("x"-1)/20+("x"-2)/30+("x"-3)/60=1`
4 x + 3(x − 1) + 2(x − 2) + (x − 3) = 60
10 x − 10 = 60
`"x"=70/10` = 70 hours.
Hence, the tank will be filled up at (4 + 7)
= 11 a.m
APPEARS IN
संबंधित प्रश्न
80% of students in a class took Statistics and 45% took Mathematics. If each student took Statistics or Mathematics and 40 took both, the total number of students in the class was:
Solve the following question and mark the best possible option.
Let a, b, c be the respective numbers that show up when three fair dice, P1, P2, and P3, are rolled. If z = |(a – 1) (b – 3) (c – 4)|,the probability that z ≤ 1 is
Solve the following question and mark the best possible option.
In a test, an examinee either guesses or copies or knows the answers to a multiple-choice question with four choices. The probability that he makes a guess is `1/3` and the probability that he copies the answer is `1/6`. The probability that his answer is correct given that he copied it, is `1/8`. Find the probability that he knew the answer to the question given that he correctly answered it.
A dice is thrown then the probability that the sum of the number is 1 or 6 is :
ln a class, there are 15 boys and 10 girls. Three students are selected at random. The probability that 1 girl and 2 boys are selected, is
In a class, 30% of the students offered English, 20% offered Hindi and 10% offered both. If a student is selected at random, what is the probability that he has offered English or Hindi?
From a pack of 52 cards, two are drawn one by one without replacement. Find the probability that both of them are kings.
A box contains 5 brown and 4 white socks. A man takes out two socks. The probability that they are of the same colour is
A card is drawn at random from a pack of playing cards. What is the probability of getting a face card?
If 10Pr = 5040, Find the value of r.
