A large cistern can be filled by two pipes P and Q in 15 minutes and 20 minutes respectively. How many minutes will it take to fill the Cistern from an empty state if Q is used for half the time and P and Q fill it together for the other half?

A water tank is three-fourth full. Pipe P can fill the empty tank in 20 minutes and pipe Q can empty the full tank in 10 minutes. If both the pipes are open, how long will it take to empty or fill the tank completely?

A cistern can be filled by 3 pipes in 30, 40, and 60 minutes respectively, and emptied by an escape pipe in 30 minutes. The three tapes are turned on at noon, but the escape pipe is at the same time accidentally left open and not closed for a quarter of an hour. At what time will the cistern be full?

Two pipes A and B would fill a cistern in 30 and 40 minutes respectively. Both pipes are opened.Determine the time the first pipe can be turned off so that the cistern may be just filled in 20 minutes?(a) After 10 minutes (b) After 15 minutes(c) After 20 minutes (d) After 22 minutes(e) After 25 minutes98. Mr. Avinash manufactures and sells a single product at a fixed price in a niche market. The sellingprice of each unit is ` 30. On the other hand, the cost, in rupees, of producing x units is 240 + bx + cx2,where b and c are some constants. Avinash noticed that doubling the daily production from 20 to 40units increases the daily production cost by 66.66 percent. However, an increase in daily productionfrom 40 to 60 units results in an increase of only 50 percent in the daily production cost. Assume thatdemand is unlimited and that Avinash can sell as much as he can produce. His objective is tomaximize the profit. How many units should Mr. Avinash produce daily?(a) 70 (b) 100 (c) 130 (d) 150 (e) 18099. Two identical circles intersect so that their centres, and the points at which they intersect, form asquare of side 2 cm. What is the area of the portion that is common to both the circles?(a) 2( – 2) cm2 (b) 2( – 1) cm2(c) 2 cm2 (d) ( – 2) cm2(e) ( – 1) cm2100. What is the number of distinct terms in the expansion of  25x y z  ?(a) 25 (b) 50 (c) 125 (d) 325 (e) 351101. There are five containers A, B, C, D and E each containing 1200 litres of water. The water is beingpumped from one tank to another as follows:From A to B at 30 litres/minuteFrom C to A at 60 litres/minuteFrom A to E at 20 litres/minuteFrom C to D at 50 litres/minuteFrom D to B at 80 litres/minuteFrom B to C at 60 litres/minuteFrom E to D at 10 litres/minuteFrom E to A at 10 litres/minuteWhich tank gets emptied first?(a) A (b) B (c) C (d) D (e) E102. In triangle DEF shown below, points A, B and C are taken on DE, DF and EF respectively such thatEC = AC and CF = BC. If angle D = 40 degress, then what is angle ACB in degrees?(a) 140 (b) 70 (c) 100 (d) 110 (e) 120103. Saga Internationals have conducted a chess competition between young boys and girls, wherein everyindividual has to play exactly one game with every other individual. It was found that in 66 games,both the players were girls, and in 210 games, both were boys. Find the number of games in which oneplayer was a boy and the other was a girl.(a) 210 (b) 222 (c) 252 (d) 276 (e) 290

Three taps A, B and C can fill a cistern in 12, 15 and 18 min respectively. They are all turned on but after 4.5 minutes A and C are turned off. How many more minutes will B take to fill the cistern?Marks : 2Negative Marks : 0Answer here1.125 min4.5 min5.625 minNone of these

Two pipes A & B can fill a cistern in 8 and 12 minutes respectively. If both the pipes are opened simultaneously, then after how much time should B be closed so that the tank is filled in 6 minutes?