M4maths Previous Puzzles

14 Oct 2022 Profit and Loss

A shopkeeper earned a profit equal to cost price of 6 items while selling 36 items together. Each item is marked at 20% above the cost price. If discount given on each item is Rs. 40, then the cost price of each item is:

OPtion

1) 1400
2) 2400
3) 1200
4) 1440
5) 2800
6) 1240
7) 1800
8) 2880
9) 2100
10) None of these

Solution

Let CP of each item =Rs. x
MP of each item = 1.2x
SP of each item = (1.2x - 40) ----(i)
CP of 36 items = 36x
SP of 36 items = (36x + 6x) = 42x
.'. SP of each item = 42x/36 = (7/6)*x ----(ii)
Comparing SP of (i) & (ii), (1.2x - 40) = (7/6)*x
Solving, we get x=1200
Correct Option 3)

Correct Option: 3 Best Solution (3)

13 Oct 2022 Arithmetic

In a bag, total of blue and red balls is equal to six times the yellow balls and blue balls are two-fifth of total of yellow and red balls. If 44 blue balls are there, then total balls in a bag are:

OPtion

1) 132
2) 254
3) 198
4) 242
5) 154
6) 286
7) 220
8) 176
9) 264
10) None of these

Solution

6Y = (B + R) ---(i)
B = (2/5)*(Y + R) ---(ii)
Given, B=44
From (i), 6Y - R = 44 ---(iii)
From (ii), Y + R = 110 ---(iv)
Solving (iii) & (iv), we get, Y=22, R=88
.'. Total balls = B + R + Y = 44 + 88 + 22 = 154
Correct Option 5)

Correct Option: 5 Best Solution (3)

12 Oct 2022 Clocks & Calendars

Dinesh was curious to know the angle between the hour and minute hands of a clock, so when he see 10:10 in a clock he calculates the shorter angle between the hands. Which of the following time will also make same angle between the hour and minute hand as calculated by Dinesh ?

OPtion

1) 9:05
2) 5:50
3) 2:35
4) 8:05
5) 3:40
6) 6:10
7) 7:10
8) 1:50
9) 4:40
10) None of these

Solution

At 10:10, minor angle between hour and minute hand = 120 - 10*(30/60) = 115°
Similarly minor angles of given times are
9:05 = 117.5°
5:50 = 125°
2:35 = 132.5°
8:05 = 147.5°
3:40 = 130°
6:10 = 125°
7:10 = 155°
1:50 = 115°
4:40 = 100°
Therefore, at 1:50 angle between hour and minute hand will be 115° which is same as the angle at time 10:10
Correct Option 8)

Correct Option: 8 Best Solution (1)

11 Oct 2022 Average

Out of twenty one persons, expenditure of eighteen persons is Rs. 120 each for their lunch and remaining three spent Rs. 30 more than the average expenditure of all the twenty one. The total money spent by all of them was:

OPtion

1) 2526
2) 3625
3) 2425
4) 2256
5) 3536
6) 2521
7) 2625
8) 3045
9) 2190
10) None of these

Solution

Let the average expenditure by 21 persons =Rs. x
Then, x = [18*120 + 3(x+30)] / 21
21x = 2160 + 3x + 90
18x = 2250
x = 125
Total spent = 21*125 = 2625
Correct Option 7)

Correct Option: 7 Best Solution (2)

10 Oct 2022 Number System

If 'P' is the greatest number.that divides 9086, 12326 and 23126 leaving the same remainder in each case. What is the sum of digits in P ?

OPtion

1) 4
2) 8
3) 6
4) 7
5) 5
6) 3
7) 9
8) 12
9) 14
10) None of these

Solution

Difference of given numbers:
12326 - 9086 = 3240
23126 -12326 = 10800
23126 - 9086 = 14040
Required number (P) = HCF of 3240, 10800 and 14040 = 1080
Hence required sum 1+0+8+0 = 9
Correct Option 7)

Correct Option: 7 Best Solution (1)

07 Oct 2022 Profit & Loss

For selling a newly purchased phone, Pankaj mark up its price by 25% above the cost price and allows three successive discounts of 6%, 8% and 10% and suffers a loss of Rs. 542, The difference between the cost price and marked price of a phone (in Rs) is

OPtion

1) 3000
2) 8000
3) 1000
4) 2000
5) 4000
6) 6000
7) 5000
8) 7000
9) 9000
10) None of these

Solution

Let CP=x, then MP=1.25x
SP with three successive discounts=1.25x*0.94*0.92*0.90=0.9729x
Loss = CP - SP
542 = x - 0.9729x
0.0271x = 542
x = 20000
.'. MP = 1.25*20000 = 25000
Hence, difference of CP and MP = 25000 - 20000 = 5000
Correct Option 7)

Correct Option: 7 Best Solution (0)

06 Oct 2022 Algebra

Which one set of operations when placed in blank places and performed sequentially will give the correct result ?
2 _ 4 _5 _ 9 _ 8 _ 5 _ 4 _ 2 = 0

OPtion

1) ÷ , - , - , x , - , + , x
2) - , + , - , ÷ , - , x , -
3) - , + , ÷ , x , - , + , ÷
4) ÷ , x , - , + , - , ÷ , +
5) ÷ , x , - , ÷ , - , + , x
6) x , + , - , ÷ , - , x , +
7) ÷ , + , - , + , - , x , +
8) x , - , + , ÷ , x , - , x
9) + , x , - , ÷ , + , x , -
10) None of these

Solution

Operations in given options when performed in sequence will give following results:
1) 2 ÷ 4 - 5 - 9 x 8 - 5 + 4 x 2 = -218
2) 2 - 4 + 5 - 9 ÷ 8 - 5 x 4 - 2 = -25
3) 2 - 4 + 5 ÷ 9 x 8 - 5 + 4 ÷ 2 = 0.833
4) 2 ÷ 4 x 5 - 9 + 8 - 5 ÷ 4 + 2 = 1.125
5) 2 ÷ 4 x 5 - 9 ÷ 8 - 5 + 4 x 2 = -3.625
6) 2 x 4 + 5 - 9 ÷ 8 - 5 x 4 + 2 = -16
7) 2 ÷ 4 + 5 - 9 + 8 - 5 x 4 + 2 = 0
8) 2 x 4 - 5 + 9 ÷ 8 x 5 - 4 x 2 = 7
9) 2 + 4 x 5 - 9 ÷ 8 + 5 x 4 - 2 = 28.5
Therefore, correct option is 7)

Correct Option: 7 Best Solution (0)

05 Oct 2022 Permutation and Combination

In how many ways the letters of the word " DUSSEHRA" can be arranged so as to form words that begin and end with a vowel ?

OPtion

1) 180
2) 720
3) 280
4) 540
5) 300
6) 270
7) 240
8) 360
9) 320
10) None of these

Solution

The word DUSSEHRA has 8 letters.
3 vowel 'UEA' can be arranged at two places (begin/end) in 3P2 = 6 ways
Now remaining 5 letters 'USSHR' in which 2 letters are same can be arranged in 5!/2! = 60 ways.
Therefore total number of ways = 6x60 = 360
Correct Option 8)

Correct Option: 8 Best Solution (0)

04 Oct 2022 Ratio & Proportion

In a quality check of a company, the number of items which passed the test and the number of those which failed were in the ratio 19:4. If later nine more items were tested and the number of failed items were 3 less than earlier, the ratio of items passed to failed was 29:5. The number of items which were initially tested is:

OPtion

1) 170
2) 138
3) 184
4) 161
5) 207
6) 133
7) 154
8) 177
9) 134
10) None of these

Solution

Let the number of items whch passed the test = 19x and number of failed = 4x
∴ Total no. of items tested = 23x
New number of items tested = 23x + 9
New number of failed items = 4x - 3
∴ New number of passed items = (23x + 9) - (4x - 3) = 19x + 12
New ratio of items passed to failed = (19x+12) / (4x-3) = 29/5
95x + 60 = 116x - 87
21x = 147
x = 7
.'. Items tested initially = 23*7 = 161

Correct Option: 4 Best Solution (2)

03 Oct 2022 Permutation & Combinations

In an inning of a T20 match, a team scores 140 runs only with the help of 4s and/or 6s. In how many ways can a team score these runs ?

OPtion

1) 18
2) 10
3) 12
4) 14
5) 16
6) 20
7) 13
8) 15
9) 9
10) None of these

Solution

Let x 4's and y 6's are scored in an inning, then 4x + 6y = 140
Here (x,y) can have values (2,22) (5,20) (8,18), (11,16) (14,14) (17,12) (20,10) (23,8) (26,6) (29,4) (32,2) (35,0), Total 12
Thus in 12 ways 140 runs can be scored with the help of 4s and 6s only.

Correct Option: 3 Best Solution (3)