There are many types of Logical puzzles & Maths Puzzles asked in various types of Aptitude Exams. These types of questions are also a common phenomenon in 11 Plus exam. Champs Learning teacher explained it well as “These are the questions where you have to decode someone else’s logic”.
Alphabet Series: These types of questions are most frequently asked in Logical puzzles section of most of the competitive exams.
The Alphabet: The English alphabet contains 26 letters. The first half that is the first 13 letters are from A to M & the second half that is last thirteen letters are from N to Z.
EJOTY: For convenience, it is advisable to remember a simple acronym called EJOTY. With the help of this acronym, we can easily find the position of any letter in the alphabet without much effort.
E – 5th, J – 10th, O – 15th, T – 20th, Y – 25th
Now for instance, we wish to find the 12th letter from the left side. We know that O is the 10th letter. Therefore, L will be the 12th letter of the alphabet.
Finding Positions: You get the questions like these much more commonly in these tests, which provides you alphabetical positions from the right side.
Let us say that there are seven boys standing in a row, ABCDEFG. If we see that C is standing on 3rd position from the left while standing 5th from the right. The sum of both the positions is 5+ 3 = 8 while total number of students is 7. So if position is given from Left side, subtract it from total number of students and then add one. This will give you the position from the right side.
Number Series: These types of questions are also very often asked in Logical Puzzles section of Aptitude exams.
There are a few examples given of Number series:
Example 1: Find the next number in the series:
101, 102, 104, 107, 111, 116….
In the example above we can see that differences between two consecutive terms given are 1, 2, 3, 4 & 5 respectively. Therefore the next difference has to be 6. The next term therefore should be 116 + 6 = 122.
Example 2: Find the next term in the series:
1, 3, 8, 19, 42…
In this example we can see that second term is given by multiplying first term by 2 and then adding 1, third term is given by multiplying second term by 2 and then adding 2, next multiplying by 2 and then adding 3, then multiplying by 4 and then adding 4, so next term has to be 42 * 5 = 170 + 1 = 171.
Example 3: Find the next term in the series:
4, 2, 2, 3, 6, 15, 45…
In the above example,
4*0.5 = 2
2*1= 2
2* 1.5 = 3
3*2 = 6
6* 2.5 = 15
15 * 3 = 45
Therefore, next term will be 45 * 3.5 = 157.5
Practice questions
A. Answer the following questions on Logical Puzzles based on the instructions given
RQP, ONM, LKJ, _____, FED
A. IHG B. CAB C. JKL D. GHI
Answer & Explanation
Sol: Option A
B. This sequence consists of letters in the reverse alphabetical order
KBJ, LCK, MDL, NEM, _____
A. OEP B. OFN C. MEN D. PFQ
Answer & Explanation
Sol: Option B
C. This series is an alternating series in alphabetical order. The 2nd letters follow the order BCDEF. The 1st and 3rd letters are alphabetical beginning with K. The 3rd letter is repeated as a 1st letter in each subsequent 3-letter segment.
Team A has scored more goals than Team B
Team C has scored fewer goals than Team B
Team A has scored fewer goals than Team C.
If the first two statements are true, the third statement is
A. True B. False C. Uncertain
Answer & Explanation
Sol: Option B
D. From the first two statements, we know that of the three teams, Team A has the scored the highest number of goals, so the third statement is necessarily false.
CDC, EFE, GHG, IJI
A. KLK B. HJH C. IJI D. JHJ
Answer & Explanation
Sol: Option A
E. This sequence consists of a simple alphabetical order with the first 2 letters of all segments: C, D, E, F, G, H, I, J, K, L. The third letter of each segment is a repetition of the 1st letter. Find the next number in the sequence:
3, 6, 9, 30, 117......
- 192 B. 352 C. 388 D. 588
Answer & Explanation
Sol: Option D
3 * 1 + 3 = 6
6 * 2 – 3 = 9
9 * 3 + 3 = 30
30 * 4 – 3 = 117
117 * 5 + 3 = 588
F. Raju weighs less than Farhan.
Raju weighs more than Bunty.
Of the three friends, Bunty weighs the least.
If the first two statements are true, the third statement is
A. True B. False C. Uncertain
Answer & Explanation
Sol: Option A
According to the first two statements, Farhan weighs the most and Bunty weighs the least.
G. Find the next number in the sequence:
104, 109, 115, 122, 130.....
A. 119 B. 125 C. 139 D. 134
Answer & Explanation
Sol: Option C
104 + 5= 109
109 + 6 = 115
115 + 7 = 122
122 + 8 = 130
130 + 9 = 13
H. Find the next number in the sequence:
26, 63, 124, 215, 342.....
A. 416 B. 511 C. 686 D. 559
Answer & Explanation
Sol: Option B
All the numbers in the sequence are 1 less than the cubes of 3, 4, 5, 6, 7, 8. Therefore, 511 is the answer.
I. Find the next number in the sequence....
15, 31, 63, 127, 255.
A. 110 B. 170 C. 511 D. 181
Answer & Explanation
Sol: Option C
15 * 2 + 1 = 31
31 * 2 +1 = 63
63 * 2 + 1= 127
127 * 2 + 1= 255
255 * 2 + 1 = 511
J. John has more coins than Jenny.
Jenny has fewer coins than Danny.
Danny has more coins than John.
If the first two statements are true, the third statement is
A. True B. False C. Uncertain
Answer & Explanation
Sol: Option B
If the first two sentences are true, both John and Danny have more coins than Jenny. However, it is uncertain as to whether Danny has more coins than John.