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2 solved questions on Sequencing Puzzle
CSS 2026General Science & AbilityQ. 7
(a) Five researchers (A, B, C, D, E) sit in a circle. A sits second to the right of C. B is not a neighbour of A. D sits opposite C. Construct a logically valid seating arrangement. Explain each step leading to your conclusion. (b) A mixture contains water and chemical X in the ratio 5 : 3. If 20 Liters of water are added, the ratio becomes 3 : 2. Determine the original amount of the mixture and the initial quantities of both components. (c) Four machines (X, Y, Z, W) must run in sequence with constraints: Y cannot run before X. Z must run immediately after W. X cannot be last. Construct all valid permutations. Explain your reasoning systematically. (d) A doctor uses a decision tree to diagnose a disease based on symptoms S1, S2, and S3. If S1 is present, test for S2. If S2 is absent, rule out the disease. If S3 is present with S2, confirm diagnosis. Construct the decision tree and explain the reasoning behind each branching decision.
#cssnexus #Circular Seating Arrangement #Mixture Problems #Ratio and Proportion
CSS Nexus6 Nov 2026
CSS 2019General Science & AbilityQ. 8
(a) Seven piano students T, U, V, W, X, Y and Z are giving a recital and their instructor is deciding the order in which they will perform; each student will play exactly one piece, a piano solo. The instructor must observe the following restrictions: X cannot play first or second; W cannot play until X has played; neither T nor Y can play seventh; either Y or Z must play immediately after W; V must play immediately after, or immediately before, U. If V plays first, which one of the following must be true? T plays sixth; X plays third; Z plays seventh; T plays immediately after Y; W plays immediately after X. (b) U = {whole numbers from 10 to 24}, A = {even numbers}, B = {numbers divisible by 5}. Write down the number of elements of A∩B. (c) In the given Venn diagram, A represents Americans, S represents scientists and P represents politicians, with regions labelled a to g. Identify: (i) Americans who are politicians but not scientists. (ii) Scientists who are politicians but not Americans. (d) Each packet of washing powder carries a token and 4 tokens can be exchanged for a free packet. How many free packets will I receive if I buy sixty four packets?
#cssnexus #Analytical Reasoning #Logic Puzzle #Sequencing Puzzle
CSS Nexus6 Nov 2026