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ব্যাংক নিয়োগ প্রস্তুতি ⎯ লং কোর্স

পরীক্ষাব্যাংক নিয়োগ প্রস্তুতি ⎯ লং কোর্সতারিখতারিখ অনির্ধারিতসময়45 minutes
মোট প্রশ্ন২৩
সিলেবাস
Math - 04 - Ratio & Proportion, Partnership, Allegation or Mixture
ঘনত্ব
উত্তর
উত্তরিতবর্তমানপুনরায় দেখুনঅসম্পূর্ণ

ব্যাংক নিয়োগ প্রস্তুতি ⎯ লং কোর্স

ব্যাংক নিয়োগ প্রস্তুতি ⎯ লং কোর্স · তারিখ অনির্ধারিত · ২৩ প্রশ্ন

.
A jar contains white, red and green marbles in the ratio of 2 : 3 : 5. Six more green marbles are added to the jars, and then the ratio becomes 2 : 3 : 7. How many white marbles are there in the jar?
  1. ক) 2
  2. খ) 3
  3. গ) 4
  4. ঘ) 5
  5. ঙ) 6
ব্যাখ্যা

W : R : G = 2 : 3 : 5 [Initial]
W : R : G = 2 : 3 : 7 [Final]
Let, Initial Green = 5x Final Green = 7x
ATQ,
(7x - 5x) = 6
=> 2x = 6
=> x = 3
So, white marbles in the jar = (2 × 3) = 6

.
The annual incomes and expenditures of a man and his wife are in the ratio of 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 the income of the husband?
  1. ক) 2000
  2. খ) 3000
  3. গ) 4000
  4. ঘ) 5000
  5. ঙ) 6000
ব্যাখ্যা

Let, annual income of husband and wife respectively = 5x and 3X
Annual expenditure husband and wife respectively = 3y and y
Saving of wife = (3x - y)
Saving of husband = (5x - 3y)
ATQ,
3x - y = 2000
=> y = (3x - 2000)
And,
5x - 3y = 2000
=> 5x - 3(3x - 2000) = 2000
=> 5x - 9x + 6000 = 2000
=> x = 1000
So, Husband's Income = 5 × 1000 = 5000

.
Three containers A, B and C are having mixtures of milk and water in the ratio 20 : 28, 18 : 30 and 8 : 40 respectively. Find the ratio of milk to water, if the mixtures of all the three containers are mixed together?
  1. ক) 6 : 5
  2. খ) 5 : 6
  3. গ) 53 : 115
  4. ঘ) 23 : 49
  5. ঙ) None of the Above
ব্যাখ্যা

At, A ; M : W = 20 : 28 = 5 : 7 = 5/12 : 7/12
At, B; M : W = 18 : 30 = 3 : 5 = 3/8 : 5/8
At C ; M : W = 8 : 40 = 1 : 5 = 1/6 : 5/6
M : W = (5/12 + 3/8 + 1/6) : ( 7/12 + 5/8 + 5/6)
= (20 + 18 + 8)/48 : (28 + 30 + 40)/48
= 46 : 98
= 23 : 49

.
Alloy A contains 40% gold and 60% silver. Alloy B contains 35% gold and 40% silver and 25% copper. Alloys A and B are mixed in the ratio of 1 : 4. What is the ratio of gold and silver in the newly formed alloy?
  1. ক) 11 : 9
  2. খ) 20 : 30
  3. গ) 9 : 11
  4. ঘ) 25 : 35
  5. ঙ) 80 : 20
ব্যাখ্যা

A:: - G : S = 40 : 60
B:: - G : S : C = 35 : 40 : 25
New, G : S = {(1×40) + (4×35)} : {(40×4) + (1×60)}
= 180 : 220
= 18 : 22
= 9 : 11 [Answer. ]

.
A, B and C enter into partnership by making investments in the ratio of 3 : 5 : 7. After a year, C invests another Tk. 337600 while A withdraws Tk.45600. The ratio of investments then changes to 24 : 59 : 67. How much did A invest initially?
  1. ক) 10000
  2. খ) 12000
  3. গ) 141600
  4. ঘ) 14900
  5. ঙ) None Of the Above
ব্যাখ্যা

Let, A : B : C = 3x : 5x : 7x
After 1 year C investment = 7x + 337600
After 1 year A investment = 3x - 45,600
ATQ,
(3x − 45600)/5x = 24/59
=> 59 × (3x - 45,600) = 120x
=> 177x - 120x = 45600 × 59
=> 57x = 45600 × 59
=> x = 800 × 59 = 47,200
A's initial investment was = 47,200 × 3 = 141600 [Answer.]

.
‘X’ Liters of the mixture contains Milk and Water in the ratio of 4 : 3. If 13 liters of Water is added then the ratio becomes 1 : 1. Then what is the final quantity of water in the mixture?
  1. ক) 40
  2. খ) 42
  3. গ) 48
  4. ঘ) 52
  5. ঙ) 54
ব্যাখ্যা

Let,
Initial milk = 4x
Initial water = 3x
ATQ,
(3x + 13)/4x = 1/1
Or, 4x = 3x + 13
Or, x = 13
So, water at final = (3 × 13) + 13
= 52 L

.
The ratio of Solution “A” and Solution “B” in the container is 3 : 2 when 10 liters of the mixture is taken out and is replaced by the Solution “B”, the ratio become 2 : 3. The total quantity of the mixture in the container is:
  1. ক) 20
  2. খ) 25
  3. গ) 30
  4. ঘ) 35
  5. ঙ) 40
ব্যাখ্যা

Ration of A : B = 3 : 2
10 L taken out and replaced by B
So, A remain = 3x - 3×10/5 = 3x - 6 And
B remain = 2x - 2×10/5 +10
= 2x + 6
ATQ,
(3x - 6)/(2x + 6) = 2/3
Or, 9x - 18 = 4x + 12
Or, 5x = 30
or, x = 6
The total quantity of mixture = (3x + 2x) = 5x = 5 × 6 = 30 L [Answer.]

.
Rice worth Tk. 126 per kg and Tk. 134 per kg are mixed with a third variety in the ratio 1 : 1 : 2. If the mixture is worth Tk. 177 per kg, the price of the third variety per kg will be:
  1. ক) Tk 224
  2. খ) Tk 200
  3. গ) Tk 250
  4. ঘ) Tk 150
  5. ঙ) Tk 75
ব্যাখ্যা

Let, the price of third variety = x
ATQ,
Or, 126×1 + 134×1 + x×2 = 177×4
Or, 260 + 2x = 708
Or, 2x = 448
Or, x = 224 [Answer.]

.
A 144 liters of mixture contains milk and water in the ratio of 5 : 7. How much milk needs to be added to this mixture so that the new ratio is 23 : 21 respectively?
  1. ক) 30
  2. খ) 32
  3. গ) 34
  4. ঘ) 36
  5. ঙ) 38
ব্যাখ্যা

Milk = 144 × 5/12 = 60L
Water = (144 - 60) = 84 L
ATQ,
(60 + x)/(144 + x) = 23/44
Or, 2640 + 44x = 3312 + 23x
Or, 21x = 672
Or, x = 672/21
or, x = 32L

Solution 2:
ATQ,
(60 + x)/84 = 23/21
Or, 60×21 + 21x = 23×84
Or, 21x = 672
or, x = 32 L

১০.
A sugar solution of 3 liters contains 60% sugar. One liter of water is added to this solution. Then the percentage of sugar in the new solution is:
  1. ক) 18%
  2. খ) 32%
  3. গ) 40%
  4. ঘ) 45%
  5. ঙ) 49%
ব্যাখ্যা

In 3 L solution sugar is 60%
So, Sugar Amount = 3 × 3/5 = 1.8 L
Now, 1 L water is added.
So, Total solution = (3 + 1)
= 4 L
% sugar = (1.8 × 100)/4
= 180/4
= 45% [Answer.]

১১.
The annual salary of A, B, C is in the proportion of 3 : 4 : 5. If C's annual salary is Tk 80000 more than that of A, then B's monthly salary is-
  1. ক) Tk 13666.67
  2. খ) Tk 13333.33
  3. গ) Tk 14373.67
  4. ঘ) Tk 16666.67
  5. ঙ) None of the above
ব্যাখ্যা

Let the annual salary of A, B, C respectively be 3x, 4x and 5x.
Then 5x - 3x = 80000
x = 40000
So, B's annual salary = 4x = Tk. 160000
Hence, B's monthly salary
= Tk (160000)/12
= Tk. 13333.33

১২.
Tk. 700 is received among A,B and C so that A receives half as much as B and B half as much as C. Then C’s share is:
  1. ক) 200
  2. খ) 300
  3. গ) 400
  4. ঘ) 500
  5. ঙ) 600
ব্যাখ্যা

Let C = x
Then B = x/2
and A = x/4
A : B : C = 1 : 2 : 4
C's share = Tk. (4/7 × 700) = 400

১৩.
If A : B = 2 : 3, B : C = 4 : 5, C : D = 5 : 9 then A : D = ?
  1. ক) 11 : 17
  2. খ) 8 : 27
  3. গ) 5 : 9
  4. ঘ) 2 : 9
  5. ঙ) 9 : 2
ব্যাখ্যা

A/D = (A/(B × B))/((C × C)/D)
= (2/(3 × 4))/((5 × 5)/9)
= (2 × 4 × 5)/(3 × 5 × 9)
= 8/27
= 8 : 27

১৪.
In a bag, there are coins of 25 p, 10 p and 5 p in the ratio of 1 : 2 : 3. If there is Tk. 30 in all, how many 5 p coins are there?
  1. ক) 50
  2. খ) 100
  3. গ) 150
  4. ঘ) 200
  5. ঙ) 250
ব্যাখ্যা

Let the number of 25 p, 10 p and 5 p coins be x, 2x, 3x respectively.
Then, the sum of their values = Tk. (25x/100) + (10 × 2x/100) + (5 × 3x/100) = Tk. 60x
Or, 60x/100 = 30
Or, x = (30 x 100)/60 = 50.
Hence, the number of 5 p coins = (3 x 50) = 150.

১৫.
Gold is 19 times as heavy as water and copper 9 times as heavy as water. The ratio in which these two metals be mixed so that the mixture is 15 times as heavy as water is :
  1. ক) 1:2
  2. খ) 2:3
  3. গ) 3:2
  4. ঘ) 19:135
  5. ঙ) None of the above
ব্যাখ্যা


Required ratio 6 : 4 = 3 : 2
১৬.
1 year ago the ratio between A’s salary and B’s Salary was 3 : 4.Ratios of their individual salaries between last year’s and present year’s are 4 : 5 & 2 : 3 respectively. At present the total of their salary is Tk 4160. The salary of A now is:
  1. ক) 1040
  2. খ) 1600
  3. গ) 2560
  4. ঘ) 3120
  5. ঙ) None of the above
ব্যাখ্যা

Present ratio of A & B
A : B
3 × (5/4) : 4 × (3/2)
= 15/4 : 12/4
= 15 : 24
= 5 : 8

A’s present salary = ( 4160 of 5/13) = 1600

১৭.
The salaries of A, B, and C are in the ratio of 1 : 2 : 3. The salary of B and C together is Tk. 6000. By what percent is the salary of C more than that of A?
  1. ক) 100%
  2. খ) 200%
  3. গ) 300%
  4. ঘ) 600%
  5. ঙ) 350%
ব্যাখ্যা

Let the salaries of A, B, C be x, 2x and 3x respectively.
Then, 2x + 3x = 6000
=> x = 1200.
A's salary = TK. 1200, B's salary = TK. 2400, and Cs salary TK. 3600.
Excess of C's salary over A's = [(2400/1200) x 100]
= 200%.

১৮.
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:
  1. ক) 150
  2. খ) 160
  3. গ) 170
  4. ঘ) 180
  5. ঙ) 200
ব্যাখ্যা

A : B : C = 7 : 8 : 11.
Hire charges paid by B = Tk. (520 × 8/26)
= Tk. 160.

১৯.
Three friends had dinner at a restaurant. When the bill was received, Akhi paid 2/3 as much as Mira paid and Mira paid 1/2 as much as Lamia paid. What fraction of the bill did Mira pay?
  1. ক) 11/3
  2. খ) 2/13
  3. গ) 3/11
  4. ঘ) 13/4
  5. ঙ) 4/13
ব্যাখ্যা

Let Mira paid x,
so, Akhi paid 2x/3, and
Lamia paid 2x,
So total bill paid is given by,
x + (2x/3) + 2x = 1;
we get,
x = 3/11

So, Mira paid 3/11 fraction of the total bill.

২০.
A mixture of 150 liters of wine and water contains 20% water. How much more water should be added so that water becomes 25% of the new mixture?
  1. ক) 10 liters
  2. খ) 20 liters
  3. গ) 30 liters
  4. ঘ) 40 liters
  5. ঙ) 50 liters
ব্যাখ্যা

Number of liters of water in 125 liters of the mixture = 20% of 150 = 1/5 of 150 = 30 liters
Let us assume that other ‘P’ liters of water are added to the mixture to make water 25% of the new mixture.
So, the total amount of water becomes (30 + P) and
the total volume of the mixture becomes (150 + P)
Thus,
(30 + P) = 25% of (150 + P)
Solving, we get P = 10 liters

২১.
The ratio of water and alcohol in two different containers is 2 : 3 and 4 : 5. In what ratio we are required to mix the mixtures of two containers in order to get the new mixture in which the ratio of alcohol and water be 7 : 5?
  1. ক) 7:3
  2. খ) 5:3
  3. গ) 8:5
  4. ঘ) 2:7
  5. ঙ) 3:5
ব্যাখ্যা

W1 : A1 W2 : A2 …… WN : AN
2 : 3 4 : 5 …… 5 : 7
W1/(W1+A1) = 2/5 ; W2/(W2+A2) = 4/9; WN/(WN+AN) = 5/12
= 72/180
= 80/180
= 75/180



=> 5 : 3
Therefore, the ratio is 5 : 3

২২.
A dog takes 3 leaps for every 5 leaps of a hare. If one leap of the dog is equal to 3 leaps of the hare, the ratio of the speed of the dog to that of the hare is:
  1. ক) 9 : 5
  2. খ) 2 : 3
  3. গ) 4 : 7
  4. ঘ) 5 : 6
  5. ঙ) 5 : 9
ব্যাখ্যা

Dog : Hare = (3 × 3) leaps of hare : 5 leaps of hare
= 9 : 5.

২৩.
In a college, the ratio of the number of boys to girls is 8 : 5. If there are 160 girls, the total number of students in the college is
  1. ক) 100
  2. খ) 150
  3. গ) 250
  4. ঘ) 260
  5. ঙ) 416
ব্যাখ্যা

Let the number of boys and girls be 8x and 5x.
Total number of students = 13x
= 13 × 32
= 416.