Number, Ranking and Time Sequence Test Questions and Answers

Answer: A

There are 49 students in the class.

If Mahesh is 15th from the bottom, there are 14 students below him; if he is 35th from the top, there are 34 above him. Counting him once:

\[ \begin{aligned} \text{total} &= 15 + 35 - 1 \\ &= 49 \end{aligned} \]

50 counts Mahesh twice, and 51 and 48 come from adding or subtracting one too many.

Answer: C

In a class of 35, Kamal is 7th from the bottom, which is 29th from the top, and Suresh is 9th from the top. Ramesh stands exactly midway, at the 19th place from the top.

Counting the places from Ramesh to Kamal inclusively, Kamal is the 11th from Ramesh (19th to 29th), which is option C, the final key. The plain difference of 10, option B, was the booklet tick that the final key changed.

Counting the line from the top, Suresh is 9th, Kamal is 29th (35 - 7 + 1), and Ramesh is at the middle place 19. Counting inclusive from Ramesh to Kamal the position is 11th, which is the final key. The simple difference of 10 would be correct if the question asked how many places are between them plus one less.

Answer: D

The oldest of all is E.

Write each statement as an inequality, with > meaning 'older than':

• A is older than B but younger than C: C > A > B.
• D is younger than E but older than A: E > D > A.
• C is younger than D: D > C.

Combining them gives the full order E > D > C > A > B, so E is the oldest and B the youngest.

D is only the second oldest, because the second statement places E above D. A sits in the middle and B at the bottom, so neither can be the oldest.

Answer: A

There are 33 boys in the row.

After they interchange, Srinath stands where Venut stood, and that place is 22nd from the left. Venut's old place was also 12th from the right. So one position is 22nd from the left and 12th from the right:

\[ 22 + 12 - 1 = 33 \]

The 1 is subtracted because that boy's place is counted from both ends. Srinath's original place, 7th from the left, is not needed for the count. Adding 22 and 12 without subtracting gives 34, which is not an option; 43, 37 and 51 match no correct working.

Answer: B

There are 37 boys in the class.

The boy is 19th from each end, so there are 18 boys on each side of him:

\[ 18 + 1 + 18 = 37 \]

Equivalently, total = position from left + position from right \(-\) 1 \(= 19 + 19 - 1 = 37\). 38 would count the boy twice and is not offered; 27, 39 and 47 do not fit the symmetric position at all, since the total must be odd with him in the exact middle.

Answer: C

C occupies the middle position.

Put the four conditions together, from tallest to shortest:

• E is the tallest of all.
• D is taller than C, and C is taller than A.
• A is taller than B.

So the order is E, D, C, A, B. With five people the middle seat is the third, and the third person in either direction is C.

A and B are the two shortest, at positions four and five, and D is second, so none of them sits in the middle.

Answer: C

There are 21 girls in the row.

If Nita is 11th from the left, 10 girls stand to her left; if she is also 11th from the right, 10 girls stand to her right. Counting her once:

\[ \begin{aligned} \text{total} &= 10 + 1 + 10 \\ &= 11 + 11 - 1 = 21 \end{aligned} \]

The general rule is: position from left + position from right − 1. Answering 22 counts Nita twice, and 20 or 19 leave out girls.

Answer: D

The fastest walker is Kabi.

Put the statements in order of speed:

• Ram is slower than Raju, so Raju > Ram.
• Raju walks as fast as Gora, so Raju = Gora.
• Kabi walks faster than Gora, so Kabi > Gora.

Combining them: Kabi > Gora = Raju > Ram. Kabi is ahead of everyone. Raju and Gora tie for second place, and Ram is the slowest.

Writing the comparisons as an inequality chain, as above, is the safe method for any such ordering question: it shows at once who is at each end.

Answer: B

There are Two such digits.

Write the number and its digits in ascending order, position by position:

The digits that stay in the same position are 3 (third place) and 5 (fifth place). Every other position changes, so the count is two, not one, three or four.

Remember that the repeated digit 5 appears twice in the sorted order, at the fifth and sixth places, so the comparison must be made position by position.

Answer: B

There are 27 students.

H is counted once from each end, so there are 15 students above H and 11 below.

\[ \text{total} = 16 + 12 - 1 = 27 \]

28 counts H twice, the usual slip, and 29 adds one more again.

The general rule: if a person is p-th from the top and q-th from the bottom, the total is p + q - 1.