What will come in place of the question mark (?) in the following question?

28 × 104 ÷ (28 – 21 + 6) + 3 = ?

What will come in place of the question mark (?) in the following question?

3.2% of 500 × 2.4% of ? = 230.4

What will come in place of the question mark (?) in the following question?

What will come in place of the question mark (?) in the following question?

What is the average of first twenty numbers in an Arithmetic Progression having common difference of 2.5 and first number of series is 10?

While preparing sugar syrup, Adya was instructed by her instructor to mix sugar with water in the ratio 35 ∶ 29. However while preparing it she forgot the actual ratio and instead used the ratio 29 ∶ 35. She prepared ten kg of solution. How much sugar or water will she have to mix in order to prepare the mixture as instructed?

The average of X and Y is 23 and that of Y and Z is 32. If the sum (X + Y + Z) is 5 times the number X, find the numbers X, Y and Z.

P, Q, R and S invested Rs. 3500 each in a partnership. After 6 months, P doubled his investment. Q and R invested for only 4 months of the year. S kept his investment for entire year. After a year, if Q got a profit of Rs. 200, then what was the total profit?

A man wants to invest sum of Rs.12000 for 4 years. Whether he should invest in a scheme which governs interest by simple interest of given rate of interest of 3% per annum or in the scheme which governs interest by compound interest of given rate of interest of 3% per annum. Also, find the interest.

Two boats are 20 km apart from each other in the direction of the flow of river. The speed of each boat in still water is 8 km/hr. They both start moving towards each other at same point of time. After how much time will they meet? (Assume that the river is straight and has no turns)