Question
The ages of 4 members of a family are in the year 2011
are βXβ,βX+6β,βX+12β and βX+18β. After some years Oldest among them was dead then average reduced by 2. After how many years from his death, the average age will same as in 2011?Solution
Average of all in 2011 = {X + (X+6) + (X+12) + (X+18)}/4 = (4X + 36)/4 = X + 9 Let the oldest die after N years, then average of three persons, {X + (X+6) + (X+12) + 3N}/3 = (X+9-2) (3X+18+3N)/3 = X+7 X+6+N = X+7 N = 1 years Let after another M years, their average will be equal to that in 2011. So, (3X+18+3N+3M)/3 = X+9 (3X + 18 + 3x1 + 3M)/3 = X+9 X + 6 +1 +M = X+9 M = 2 years
In the following question, a group of letters is given which are numbered 1, 2, 3, 4, and 5. Select that combination of numbers so that letters arranged...
In a certain code language, βyou are a good friendβ is coded as βes an pz fd mqβ and βhis friend is very kindβ is coded as βck mq pn ag sb...
Who sits right between Varu and Sita?
There are six persons viz. W, X, Y, Z, A and B; all are of different heights but not necessarily in the same order. Xβs height is 180 cm and he is tal...
How many persons sits between V and S when counted anticlockwise from V?
Read the given statements and conclusions carefully. Assuming that the information given in the statements is true, even if it appears to be at variance...
Select the set in which the numbers are NOT related in the same way as are the numbers of the given set. (NOTE: Operations should be performed on the wh...
L, M, N, O and P are five buses of different sizes. Two of them provide food on board, 3 are luxurious buses and 3 are air conditioned buses. One has ca...
When the below given diagram is folded in the shape of a cube which symbol will face opposite to β^β?
What should come in place of ? in the given series based on the English alphabetical order?
ACE, FHJ, KMO, PRT , ?
Relevant for Exams:
