Question
Pipes X and Y can fill a tank in 48 minutes and 80 minutes
respectively. Another pipe Z can empty the tank in 2 hours. X and Z are opened together. If after 36 minutes, Y is also opened, then how long will it take to fill the tank completely?Solution
ATQ,
Let the capacity of the tank be 240 litres (LCM of 48, 80 and 120)
Efficiency of X = 240 ÷ 48 = 5 litres/minute
Efficiency of Y = 240 ÷ 80 = 3 litres/minute
Efficiency of Z = 240 ÷ 120 = -2 litres/minute (since it is an outlet pipe)
Tank filled in 36 minutes = (5 - 2) × 36 = 108 litres
Remaining tank to be filled = 240 - 108 = 132 litres
Time to fill remaining = 132 ÷ (5 + 3 - 2) = 132 ÷ 6 = 22 minutes
Total time taken = 36 + 22 = 58 minutes
Income of A is twice the income of B. B and A spend 55% and 65% respectively of their incomes. Find the savings of A, if B saves Rs. 18000 in a month.
A and B together can finish a task in 12 days. B and C together can complete the same task in 20 days. A and C together complete 33(1/3) ​ % of the ta...
The sides of a triangle are 9 cm, 12 cm, and 15 cm. What is the area of the largest circle that can be inscribed in this triangle?Â
A businessman bought goods for Rs 1050 and sold them on the same day for Rs 1228.5 on credit for 10 months, thus earning a profit of 4%. Find the rate o...
What is the primary purpose of an operating system in a computer system?
13, 91, 108, 756, ?, 5411
The function f(x)=x3 −62x2+ax+9 has a local maximum at x=1. Then the value of a is:
The curved surface area of a right circular cylinder with a radius of 7 cm is 440 cm². If the height of the cylinder is increase...
Let a plane pass through the point (1, –1, 2) and is perpendicular to the vector 2i + j − 2k. Then its Cartesian equation is:
'Symbian' is a_______
Relevant for Exams:
