M4maths Previous Puzzles

22 Nov 2019 Numbers

How many of the following numbers are divisible by 132?

264, 396, 462, 792, 968, 2178, 5184, 6336, 1058, 1188, 1056

OPtion

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

Solution

264, 396, 792, 6336, 1188, 1056

Correct Option: 8 Best Solution (0)

21 Nov 2019 Numbers

What least number must be added to 1056, so that the sum is completely divisible by 23 ?

OPtion

1) 10
2) 11
3) 13
4) 15
5) 14
6) 16
7) 12
8) 17
9) 19
10) None of these

Solution

1056 = 23*46-2
So Answer is 2

Correct Option: 10 Best Solution (0)

20 Nov 2019 Volume

26.4 cubic centimeters of silver is drawn into a wire 2 mm in diameter. The length if the wire in meters will be:

OPtion

1) 8.4cm
2) 84cm
3) 84mm
4) 8400m
5) 84000cm
6) 8.4m
7) 84m
8) 0.84mm
9) 840m
10) None of these

Solution

Let the length of the wire be h
Radius=2/2 mm = 1/10 cm
Volume = πr^2h= 26.4
=> (22/7)∗(1/10)∗(1/10)∗h = 26.4
=>h = (26.4∗10∗10∗7)/22 = 840cm = 8.4m

Correct Option: 6 Best Solution (3)

19 Nov 2019 Clock

An accurate clock shows 8 o'clock in the morning. Through how may degrees will the hour hand rotate when the clock shows 1 o'clock in the afternoon?

OPtion

1) 250
2) 200
3) 225
4) 180
5) 175
6) 150
7) 120
8) 75
9) 125
10) None of these

Solution

(360/12)*5 = 150

Correct Option: 6 Best Solution (7)

18 Nov 2019 Simple Interest

A sum fetched a total simple interest of Rs. 21 at the rate of 6% p.a. in 2 years. What is the sum?

OPtion

1) 750
2) 775
3) 780
4) 975
5) 600
6) 150
7) 900
8) 1000
9) 1100
10) None of these

Solution

SI = PRT/100
21 = P*6*2/100
=> P = 175

Correct Option: 10 Best Solution (0)

15 Nov 2019 Profit & Loss

Robert Batra buys an old scooter for Rs. 11700 and spends Rs. 1800 on its repairs. If he sells the scooter for Rs. 26000, his gain percent is:

OPtion

1) 90.4%
2) 91.7%
3) 95.0%
4) 94.0%
5) 95.4%
6) 92.6%
7) 96.2%
8) 97.0%
9) 99.10%
10) None of these

Solution

Actual CP = 11700 + 1800 = 13500

SP = 26000

Gain = 26000 - 13500 = 12500

Profit % = 12500*100/13500 = ~92.6%

Correct Option: 6 Best Solution (0)

14 Nov 2019 Probability

An Integer from 299 through 1,000, both inclusive, is to be chosen at random. What is the probability that the number chosen will have 2 as at least one of its digit?

OPtion

1) 71/351
2) 73/351
3) 69/351
4) 70/351
5) 72/351
6) 66/351
7) 68/351
8) 67/351
9) 74/351
10) None of these

Solution

Total number of possible numbers between 1000 and 299 = 1000-298 = 702

Lets try to find count of numbers which will have 2.

1. First count of number which will have only one 2

a. Count of numbers with 2 at hundred place =
Fixing 2 at hundred place we have count of = 1
b. Count of numbers with 2 at ten's place =
Fixing 2 at ten's place we have count of = 7*1*9 = 63
c. Count of numbers with 2 at unit's place =
Fixing 2 at unit's place we have count of = 7*9*1 = 63

2. Next lets count numbers which will have exactly 2 two's
7*1*1 = 7



Total Count = 1+63+63+7 = 134

Probability = 134/702 = 67/351

Correct Option: 8 Best Solution (0)

13 Nov 2019 Area

If the diagonal of a rectangle is 12cm long and its perimeter is 28 cm. Find the area of the rectangle.

OPtion

1) 28
2) 22
3) 20
4) 16
5) 21
6) 23
7) 24
8) 26
9) 32
10) None of these

Solution

Let the sides of a rectangle be x & y cm, then
Diagonal² = x² + y²
144 = x² + y² ---(i)
Also, Perimeter = 2(x+y) = 28 => (x+y) = 14 ---(ii)
We know, (x+y)² = x² + y² + 2xy
=> 14² = 144 + 2xy
Solving we get
xy = 26

Correct Option: 8 Best Solution (2)

12 Nov 2019 Calendar

Today is Tuesday. After 180 days, it will be :

OPtion

1) Monday
2) Tuesday
3) Wednesday
4) Thursday
5) Friday
6) Saturday or Sunday
7) Sunday or Monday
8) Sunday
9) Saturday
10) None of these

Solution

180 days = 25 weeks 5 days
Hence if today is Tuesday, After 180 days, it will be = (Monday + 5 days)
= Saturday

Correct Option: 8 Best Solution (1)

11 Nov 2019 Compound Interest

What will be the compound interest on a sum of Rs. 200000
after 3 years at the rate of 5% p.a.?

OPtion

1) 31515
2) 31625
3) 31535
4) 31525
5) 32525
6) 33525
7) 31025
8) 31725
9) 37525
10) None of these

Solution

CI = P (1 + r/n) (nt) - P
Answer is:31525

Correct Option: 4 Best Solution (3)