For the following questions answer them individually
Two coal loading machines, each working 12 hours per day for 8 days, handle 9000 tonnes of coal with an efficiency of 90%; while 3 other coal loading machines at an efficiency of 80% are set to handle 12000 tonnes of coal in 6 days. How many hours per day should each machine
work?
Six pipes are fitted to a water tank. Some of these are inlet pipes and the others outlet pipes. Each inlet pipe can fill the tank in 9 hours and each outlet pipe can empty the tank in 6 hours. On openingall the pipes, an empty tank is filled in 9 hours. The number of inlet pipes is .......
A student purchased a computer system and a colour printer. If he sold the computer system at 10% loss and the colour printer at 20%gain, he would not lose anything. But if he sells the computer system at 5% gain and the colour printer at 15% loss, he would lose ₹800 in the bargain. How much did hepayfor the colour printer?
Suppose that a maximum of 25 gm of salt dissolves in 100 gm of water. Any more salt, if added, remains undissolved and a sediment falls at the bottom. Now, water is evaporated from 1 kg of a 4% solution at the rate of 28 gm per hour. After how long will it start sedimenting
approximately?
In a defective 6-faced die with numbers 1 to 6 inscribed, the probability of getting an odd number is twice the probability of getting an even number. Find the probability of getting a 2-digit prime number on 2 successive throws of the die.
The fuel indicator in a car shows $$\frac{1}{5}th$$ of the fuel tank as full. When 22 more litres of fuel is poured into the tank, the indicator rests at three-fourth of the full mark. What is the capacity of the fuel tank?
A sum of money is accumulating at compoundinterest at a certain rate of interest. If simple interest instead of compound were reckoned, the interest for the first two years would be diminished by ₹20 and that for thefirst three years by ₹61. What is the sum?
A jar full of milk contains 40% water, A part of this milk is replaced by another containing 19% water and now the percentage of water is found to be 26%. The quantity of milk replaced is ........
A fair coin is tossed repeatedly, If head appears on the first four tosses, then the probability of appearance of tail on the fifth toss is ..........
The electricity bill of a certain establishment is partly fixed and partly varies with the number of units of electricity consumed. When in a certain month 540 units are consumed, the bill is ₹1800. Im another month 620 units are consumed and the bill 16 ₹2040. In yet another month 500 units are consumed. Thebill for that month would be ..........