Bangladesh Bank written examination math solution for the post of officer 2015. Check below to get BB officer written exam math solutions –

**01.** A shop stocks four types of caps, there are 1/3 as many red caps as blue caps and 1/2 as many green caps as red caps. There are equal number of green caps and yellow caps. If there are 42 blue caps, then what percent of the total caps in the shop are blue?

**Solution:**

Given that, blue caps = 42

Red caps = 42/3 = 14

Green caps = 14/2 = 7

Yellow caps = 7

Total caps = 42 + 14 + 7 + 7 = 70

Percentage of blue caps = (42/70)100 = 60% Ans.

**02.** The annual incomes and expenditures of a man and his wife are in the ratios 5:3 and 3:1, respectively. If they decide to save equally and find a balance of Tk. 4000 at the end of the year, what was their income?

**Solution:**

Let, their income be 5x and 3x and their expenditure be 3x and x.

According to the question,

(5x + 3x) – (3x + x) = 4000

Or, 4x = 4000

Or, x = 1000

So, Man’s income 5x = 5*1000 =Tk. 5000

Woman’s income 3x = 3*1000 =Tk. 3000 Ans.

**03.** A person sold two articles each for the same price of Tk. 1040. He incurs 20% loss on the first and 10% loss on the second. Find his overall percentage of loss.

**Solution:**

Let, Price be Tk. 100

At, 20% loss, selling price = 100 – 20 =Tk. 80

And at 10% loss selling price = 100 – 10 =Tk. 90

So, cost of 1st item = (1040/80)100 =Tk. 1300

And cost of 2nd item = (1040/90)100 = Tk. 1155.55

Total cost of two items =Tk. (1300 + 1155.55) = Tk. 2455.55

But selling price = 1040 + 1040 =Tk. 2080.

So, loss =Tk. (2455.55 -2080) =Tk. 375.55

So, overall loss percentage = (375.55/2455.55)100 = 15.29% Ans.

**04.** If the sum of five consecutive integers is S, what is the largest of those integers in terms of S?

**Solution:**

Let, consecutive integers are x, x+1, x+2, x+3, x+4.

According to the question,

X + x + 1 + x + 2 + x + 3 + x + 4 = s

Or, 5x + 10 = s

Or, x = (s – 10)/5

Or, x + 4 = (s – 10)/5 + 4 [Add 4 both side]

Or, x + 4 = (s + 10)/5.

Or, x + 4 = s/5 + 2

So, the largest integer = s/5 + 2 Ans.

**05.** The difference between two numbers is five and the difference of their squares is 65. What is the larger number?

**Solution:**

Let, Larger number be x and smaller number be y According to the question,

x – y = 5…………………..(i)

x^2 – y^2 = 65 ……………..(ii)

Or, (x + y) (x – y) = 65

Or, (x + y)5 = 65

Or, x + y = 13……………………(iii)

From, (i)+(ii) we get,

2x = 18

Or, x = 9

Putting the value of x in (i) we get,

9 – y = 5

Or, y = 4

So, larger number = 9 Ans.

**06.** Robi drove 100 miles to visit a friend. If he had driven 8 miles per hour faster than he did, he would have arrived in 5/6 of the time, he actually took. How many minutes did the trip take?

**Solution:**

Let, Robi took x hours to cover 100 miles

Actual speed = 100/x mph [mph= Mile per hour]

New speed =(100/x + 8) mph

New time taken=x*(5/6) = 5x/6 hours.

We know, Speed × Time =Distance

(100/x + 8)*(5x/6) = 100

Or, x = 5/2 hrs = 5*60/2 = 150 mins. Ans.

**07.** Of the three numbers, second is twice the first and is also thrice the third. If the average of the three numbers is 44, then what will be the largest number?

**Solution:**

Let,1st Number = x,

2nd Number = 2x and 3rd Number = 2x/3

According to the question,

x + 2x + 2x/3 = 44*3

Or, (3x + 6x + 2x)/3= 132

Or, 11x =396

Or, x=36.

So, the largest number is = 2*36 = 72 Ans.