Number, Ranking and Time Sequence Test Questions and Answers

Answer: B

13 boys must be added.

X is counted in both positions, so the number of boys in the line is

\[ 12 + 4 - 1 = 15 \]

To make the line 28 boys long, \(28 - 15 = 13\) more must be added. 12 comes from counting X twice (12 + 4 = 16 boys), and 14 or 20 do not follow from the positions.

In general, if a person is m-th from one end of a line and n-th from the other, the line has \(m + n - 1\) people, because the person is counted in both positions.

Answer: C

The person in the middle by age is Muskan.

Kamal is older than Muskan, Muskan is older than Amal, and Amal is older than Sandhya, which gives the chain Kamal > Muskan > Amal > Sandhya. George is the eldest of all, so the full order from oldest to youngest is:

George, Kamal, Muskan, Amal, Sandhya.

With five people, the third is in the middle, and that is Muskan. George is the eldest, Kamal second and Sandhya the youngest, so none of them is in the middle.

Answer: D

The class had 55 students.

Among those who passed, Rahul is 16th from the top and 29th from the bottom, so the number who passed is

\[ \begin{aligned} \text{passed} &= 16 + 29 - 1 = 44 \\ \text{class} &= 44 + 5 + 6 = 55 \end{aligned} \]

Rahul is counted in both rankings, which is why 1 is subtracted. The class also includes the 5 who failed and the 6 who did not sit the examination. 44 is only the number who passed, and 50 leaves out the five who failed.

Answer: B

The youngest of all is Geeta.

Arrange the statements from oldest to youngest:

• Radha is younger than Sunita but older than Rita: Sunita, Radha, Rita.
• Sham is older than Rita but younger than Radha: Sunita, Radha, Sham, Rita.
• Rita is older than Geeta: Sunita, Radha, Sham, Rita, Geeta.

So Geeta comes last. Rita is the second youngest, Sham is in the middle, and Sunita is the eldest. A quicker check: Rita is younger than Radha and Sham, and Radha is younger than Sunita, so only Geeta, who is younger than Rita, can be the youngest.

Answer: A

The answer is 18, the number the positions give, as the official key has it.

Rina is 8th from the left, so 7 students stand on her left. She is 11th from the right, so 10 students stand on her right. The row is those students plus Rina herself.

The stem also says the row has 20 students, which does not agree with these two positions (they fit a row of 18). The key follows the positions, so the answer is 18; option C (20) simply repeats the figure in the stem, and options B (19) and D (21) come from slips such as forgetting to subtract Rina or adding 2 instead of 1.

Answer: C

P is 31st from the right.

Position from the right = total - position from the left + 1, because P is counted in both directions:

\[ 45 - 15 + 1 = 31 \]

There are 14 students to P's left and 30 to his right, so counting from the right, P comes after those 30, in 31st place.

30th forgets to add 1. 25th and 33rd do not follow from 45 and 15 by any correct counting.

Answer: C

Ajai's rank from the last is 15. If he ranks seventeenth from the top in a class of thirty one, there are sixteen students above him, so the number below him is the total minus his rank:

\[ 31 - 17 = 14 \]

That gives fourteen students below him, and his rank from the last is one more than that, since he himself counts:

\[ 14 + 1 = 15 \]

Option C is correct. Option B gives the number of students below him, without counting him.

Answer: C

Her earlier position from the right was 14th.

After moving four places to the right she is 12th from the left, so she was earlier 12 - 4 = 8th from the left.

\[ \text{position from right} = 21 - 8 + 1 = 14 \]

Forgetting to add 1 gives 13; 10th is her new position from the right (21 - 12 + 1), and 16th adds the four places instead of subtracting them.

Answer: A

Correct answer: Friday

From 25 June to 15 August is \( 5 + 31 + 15 = 51 \) days. Since \( 51 = 49 + 2 \), the day moves on by two from Wednesday, giving Friday.

Answer: D

Correct answer: 6 : 34

In each pair the second number is the square of the first plus two: \( 4^2+2 = 18 \), \( 7^2+2 = 51 \), \( 9^2+2 = 83 \). For 6 the rule gives \( 6^2+2 = 38 \), not 34 - so 6 : 34 is the odd pair.