A box contains 2 white balls, 3 black balls and 4 red balls. In how many ways can 3 balls be drawn from the box, if at least one black ball is to be included in the draw?
A bank offers 5% compound interest calculated on half-yearly basis. A customer deposits Tk. 1600 each on 1st July of a year. At the end of the year, how much he would have gained as interest?
Two number M and N are such that the sum of 5% of M and 4% of N is two-third of the sum of 6% of M and 8% of N. What is the ratio of M and N?
Ranu and Rabu appeared at an examination. Rabu secured 9 marks more than Ranu and her marks was 56% of the sum of their marks. The marks obtained by both of them are ---
In a class, 20% of the students are below 20 years of age. The number of students above 20 years of age is two-third of the number of students of 20 years of age which is 48. What is the total number of students in the class?
A large cube is formed from the material obtained by melting three smaller cubes of 3,4 and 5 cm side. What is the ratio of the total surface areas of the smaller cubes and the large cube?
Two trains of the same length running in opposite directions cross a man standing on the platform in 27 seconds and 17 seconds respectively andhey cross each other in 23 seconds. What is the ratio of their speeds?
From a group of 7 men and 6 women, five persons are to be selected to form a committee so that at least 3 men are there on the committee. In how many ways can it be done?
Three numbers which are co-prime to each other are such that the product of the first two is 551 and that of the last two is 1073. The sum of the three numbers is ---
The difference between a two-digit number and the number obtained by interchanging the digits is 36. What is the difference between the sum and difference of the digits of the number if the ratio between the digits the number is 1 : 2?
X, Y and Z jointly started a business. It was agreed that X would invest Tk 6,500 for 6 months, Y, Tk 8,400 for 5 months and Z, Tk 10,000 for 3 months. X wants to be the working member for which, he was to receive 5% of the profits. The profit earned was Tk 7,400. What is the share of Y in the profit?
Let N be the greatest number that will divide 1305, 4665 and 6905, leaving the same remainder in each case. Then sum of the digits in N is ---
Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5?
Albert invested an amount of Tk 8,000 in a fixed deposit scheme for 2 years at compound interest rate 5% per annum. How much amount will albert get on maturity of the fixed deposit?
Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 3 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is ----
which of the following statements is incorrect?
Which of the following number replaces the question mark?
A number consists of two digits. If the digits interchange places and the new number is added to the original number, then the resulting number will be divisible by which of the following?
A, B and C start at the same time in the same direction to run around a circular stadium. A completes a round in 252 seconds, B in 308 seconds and C in 198 seconds, all starting at the same point. After what time will they gain meet at the starting point altogether?