BCS and Bank Job Preparation: September 2015

Janata Bank Limited

Assistant Executive Officer (Teller) 2015

Mathematics

What will be the compound interest on a sum of TK. 25,000 after 3 years at the rate of 12 p.c.p.a.?

Solution: Amount=[25000×(1+12/100)³]

=(25000×28/25×28/25×28/25)

=35123.20

So, C.I.=( 35123.20-25000)

=10123.20

In a school, 10% of the boys are some in number as ¼ th of the girls. What is the ratio of boys to girls in the school?

Solution: 10% of boy=10/100 of boy =1/4 th of girl

So, boy/girl=100/(10*4)=5/2

If a number is decreased by 4 and divided by 6, the result is 8. What would be the result if 2 is subtracted from the number and then it is divided by 5?

Solution: Let, the number be x

x-4/6=8

or,x=6*8+4=48+4=52

Now, (52-2)/5=50/5=10

A 70 cm long wire is to be cut into two pieces such that one piece will be 2/5 as long as the other. How many centimeters will the shorter piece be?

Solution: Let the other piece be of length x cm, so the shorter piece = 2/5 of x =2x/5

Now, 2/5 x + x =70

Or, 7/5 x=70

Or, x=50 and 2/5 x=2/5 * 50 =20 cm

The Product of two numbers is 4107. If the H.C.F. of the these numbers is 37, then the greater number is :

Solution: Let the numbers be 37a and 37b

Then, 37a × 37 b = 4107

Or, ab = 3

Now, Co-primes with product 3 are (1,3)

So, the required numbers are (37 * 1, 37 *3) = (37, 111)

So, Greater number = 111

What will be the ratio of sample interest earned by certain amount at the same rate of interest for 6 years and that for 9 years?

Solution: Let the principal be P and rate of interest be R%

So, Required ratio = (P×R×6/100)/(P×R×9/100)

=6 PR / 9 PR

=2/3

=2:3

The average of six number is x and the average of three of these is y. If the average of the remaining three is z, then:

Solution: Average of 6 numbers = x

Sum of 6 numbers = 6 x

Average of the 3 numbers = y

Sum of the 3 numbers = 3y

Average of the remaining 3 numbers = z

Sum of the remaining 3 “ =3z

Now we know that 6x= 3y + 3z

Or, 2x = y + z

In what ratio must a grocer mix two varieties of pulses costing TK. 15 and TK. 20 per kg respectively so as to get a mixture worth TK. 16.50 per Kg?

Solution: By the rules of allegation:

Cost of Cheaper 15 TK Cost of dearer 20 TK

Mean Price

16.50 TK

(20-16.50) or, 3.50 (16.50-15) or,1.50

When a commodity is sold for TK. 34.80, there is a loss of 2%. What is the cost price fo the commodity?

Solution: Sell price = 34.80; loss = 2%

Cost price = (100 × 34.80)/98 = 35.51

[Note: Correct answer not available in the question]

How long will a boy take to run round a square field of side 35 meters, if he runs at the rate of 9 km/hr?

Solution: Total length to cover = 4 sides of the square = 4 × 35 meters

9 km/hr = 9000/(60×60 sec)

Time taken = (4 × 35 × 60 × 60)/9000 sec

=56 sec

The smallest 5-digit number exactly divisible by 41 is:

Solution: The smallest 5-digit number = 10000

If we divide 10000 by 41, 37 will be remainder

So, required number = 10000+ (41-37)= 10004

A, B, C hired a car for TK. 520 and used it for 7, 8 and 11 hours respectively. Hire charges paid by B were:

Solution: Hire charges paid by B = 520 × (8/7+8+11) = 160 TK.

The square root of 64009 is :

Solution: Square root of 64009 is 253

Which of the following is not a leap year?

Solution: The century divisible by 400 is a leap year

So, 700 is not a leap year

The ratio of the father’s age to his son’s age is 7:3. The product of their ages is 756. The ratio of their ages after 6 years will be:

Solution: Let their age be 7x and 3x

Now, 7x × 3x =756

Or, x²= 756/(7×3)= 36

Or, x = 6

After 6 year the ratio would be = (7x+6)/(3x+6)

= (7*6+6)/(3*6+6)

= 2/1

= 2 : 1

Two Pipes A and B can fill a tank in 6 hours and 4 hours respectively. If they are opened on alternate hours and if pipe A is opened first, in how many hours, the tank shall be full?

Solution: (A+B)’s 2 hour’s work when open A = 1/6 + 1/4 = 5/12

“ 1 “ “ “ = 5/12 * 2 = 5/6

Remaining work = 1-5/6 = 1/6

Now, it’s A’s turn in 5^th hour

1/6 work will be done by A in 1 hour

Total time = 4 + 1 = 5 hours

In a camp, there is a meal for 120 men or 200 children. If 150 children have taken the meal, how many men will be catered to with the remaining meal?

Solution: There is a meal for 200 children, 150 children have taken the meal.

Remaining meal is to be catered to 50 children

Now, 200 children = 120 men

50 “ =(120/200 * 50) = 30 men

(1000)⁷ ÷ 10¹⁸

Solution: (1000)⁷ / 10¹⁸ = {(10)³}⁷ / 10¹⁸ = 10²¹ / 10¹⁸ = 10^21-18 = 10³ = 1000

In a 200 meters race A beats B by 35 m or 7 seconds. A’s time over the course is:

Solution: B runs 35 m in 7 sec

B covers 200 m in (7/35 * 200) = 40 sec

B’s time over the course = 40 sec

A’s time over the course = (40-7) = 33 sec

617 + 6.017 + 0.617 + 6.0017 = ?

Solution: 617 + 6.017 + 0.617 + 6.0017 = 629.6357

The 15% of 40 is greater than 25% of a number by 2, then the number is :

Solution: 15% of 40 = 25% of number + 2

Or, (15*40)/100 -2 = 25/100 * number

Or, 6-2 = 25/100 * number =

Or, Number = (4*100)/25 = 16

A can finish a work in 18 days and B can do the same work in half the time taken by A. Then, working together, what part of the same work they can finish in a day?

Solution: Given that B alone can complete the same work in day = half the time taken by A = 9 days

A’s one day’s work = 1/18

B’s “ “ “ = 1/9

(A + B)’s one day’s work = 1/18 + 1/9 = 1/6