The weights of 4 boxes are 30, 40, 50 and 100 kilograms. Which of the following cannot be the total weight, in kilograms, of any combination of these boxes and in a combination a box can be used only once?
In a row of students, if John , who is 16th from the left, and Johnson, who is 8th from the right, interchange their positions, John becomes 33rd from left. How many students are there in a row?
In a row of students, Ankit is 26th from the left end. Poonam is 18 ranks to the right of Ankit. If Poonam is 32nd from the right end, then what will be the rank of Ankit from the right end?