Explanation:

If a-b=3 and a2+b2=29, what is the value of ab? Correct Answer 10 a2 + b2 = 29 ( a - b)2 + 2ab = 29 3a2 + 2ab = 29 9 + 2ab = 29 2ab = 29 - 9 2ab = 20 ab = 10

Explanation:

At present , father's age is 4 times more than that of his son . 6 years ago father's age was 10 times more than of his son. What is their present age? Correct Answer 36 and 9 years Let, Father’s age be F and son’s age be S F = 4S and, (F - 6) = 10(S - 6)  4S - 6 = 10S - 60  6S = 54 S = 9,F = 36

Explanation:

A starts business with TK. 3500 and after 5 months, B joins with A as his partner. After a year, the profit is divided in the ratio 2:3. What is B's contribution in the capital? Correct Answer TK. 9000 Let, the capital of B = x tk According to the question, (3500×12) /7x = 2/3 14x = 3500×12 x = ( 3500×12×3)/14 x = 9000 Tk.

Explanation:

What is the smallest number that should be added to 4456 so that the sum is completely divisible by 6? Correct Answer 2 The diviisible smallest number = ( 4456 + 2)/6 = 743 so required smallest number is 2.

Explanation:

A fruit seller had some apples. He sold 40% of he apples and still has 420 apples left. How many apples did he have initially? Correct Answer 700 Apples remain unsold = ( 100 - 40) = 60% 60% = 420 apples 1 % = 420/60 apples 100% = ( 420×100)/60 apples = 700 apples He hand 700 apples initially.

Explanation:

The population of a town increased from 1,75,000 to 2,62,500 in a decade. The average percentage increase of the population per year is---- Correct Answer 5% The population increased in 10 years = 262500 - 175000 = 87500 The population increased in 1 years = 87500/10 Now, By 175000 peoples 1 years increased 8750 By 1 peoples 1 years increased = 8750/175000 By 100 peoples 1 years increased = ( 8750×100)/175000 = 5%

Explanation:

In the figure at the right end, PS is perpendicular to QR. IF PQ=PR and PS = 24, then QR=? Correct Answer 20 PQ2 + PS2 + QS2⇒QS2 = (26)2 - (24)2 = (26 + 24)(26 - 24) = 100⇒QS = √100 = 10∴QS = 10×2 = 20 [∵QS = SR;QR = 2QS]

Explanation:

In the figure below, the value of y is _ Correct Answer 42 ⇒ 2x + 3x  =  180 ⇒ 5x  =  180 ⇒ x  =  36 Again, y + 30  =  2x  =  72 ⇒ y  =  42

Explanation:

The sum of ages of 5 children born at intervals of 3 years each is 50 years. What is the age of the youngest child? Correct Answer 4 years Let, The age of the youngest child = x year The age of the 2nd children = ( x + 3) year The age of the 3rd children = ( x + 3 + 3) year Tne age of the 4th children = ( x + 6 + 3) year The age of the 5th children = ( x + 9 + 3) year According to question, x + x + 3 + x + 6 + x + 9 + x + 12 = 50 5x + 30 = 50 5x = 50 - 30 5x = 20 x = 4 So, the age of the youngest child is 4 years.

Explanation:

The average age of a husband, wife and their child 3 years ago was 27 years and the average age of the wife and the child 5 years ago was 20 years. What is the percent age of the husband? Correct Answer 40years 3 years ago their average age was = 27 years At present their average age = ( 27 + 3) = 30 years At present the summation of their age = 30×3 = 90 years Again, 5 years ago, the average age of child and wife was = 20 years At present their average age = 20 + 5 = 25 years. At present the summation of their age = 25×2 = 50 years So, at present the husbands age = 90 - 50 = 40 years

Explanation:

Running at the same constant rate, 6 identical machines can produce a total of 270bottles per minute. At this rate, how many bottles could 10 such machines produce in 4 minutes? Correct Answer 1800 6 identical machines in 1 minutes can produce 270 bottles 1 identical machines in 1 minutes can produce 270/6 bottles 10 indentical machines in 4 minutes can produce = ( 270×4×10)/6 = 1800 bottles

Explanation:

A tank is filled in 5 hours by three pipes A, B and C . The pipe C is twice as fast as B and B is twice as fast as A. How much time will pipe A alone take to fill the tank? Correct Answer 35 hours Let, Pipe C need to fill the tank = x hours Pipe B need to fill the tank = 2x hours Pipe, A need to fill the tank = 4x hours ( A + B + C) together at 1 hour fill 1/5 portion Again, C fill the tank at 1 hour = 1/x portion B fill the tank at 1 hour = 1/2x portion A fill the tank at 1 hour = 1/4x portion According to question, 1/x + 1/2x + 1/4x = 1/5 ( 4 + 2 + 1)/4x = 1/5 7/4x = 1/5 4x = 35 x = 35/4 Pipe A take to fill the tank = 4x = 4 × 35/4 = 35 hours

Explanation:

If P = 5+2 then the value of P2 is Correct Answer 27+102 p = 5 + √2 p2 = ( 5 + √2) 2 p2 = 52 + 2.5.√2 + ( √2)2 p2 = 25 + 10√2 + 2 p2 = 27 + 10 √2

Explanation:

Six bells commence tolling together and toll at intervals of 2,4,6,8,10 and 12 seconds respectively. In 30 minutes, how many times do they toll together? Correct Answer 15 The L.C.M of 2, 4, 6, 8, 10, 12 = 120 So, after 120 seconds later they toll together. Now, At 120 seconds toll it 1 times At 1 seconds toll it 1/120 times At 1800 seconds toll it ( 1800/120) = 15 times

Explanation:

If 12a + 3b =1 and 7b-2a=9, what is the average of a and b? Correct Answer 0.5 12a + 3b = 1........... (1) 7b - 2a = 9........... (2) (1) + (2) = 10a + 10b = 10 a + b = 10/10 = 1 a + b/2 = 1/2 a + b/2 = 0.5 a এবং b এর গড় হলো 0.5

Explanation:

If one-third of one -fourth of a number is 15, then three-tenth of that number is-- Correct Answer 54 Let, the number = x According to the question, 1/3 of x of 1/4 = 15 1/3 × x ×1/4 = 15 x/12 = 15 x = 180 The three - tenth of that number = x of 3/10 = 180×3/10 = 54

Explanation:

If the salary of an employee is reduced by 10 percent for his late attendance and then increased by 10 percent on a pardon , how much does he lose? Correct Answer 1% এখানে, শতকরা হ্রাস পেলো = 10 - 10 - 10 × 10/100 = - 1% সু্তরাং, শতকরা 1% হ্রাস পেল।

Explanation:

An amount of money at simple interest amounts to TK. 815 in 3 years and to TK> 854 in 4 years. The amount is -- Correct Answer TK. 698 Capital + 4 years interest = 854 Tk. Capital + 3 years interest = 815 Tk. ( - ) 1 year interest = 39 Tk. 4 year interest = 39×4 = 156 Tk. Capital = 854 - 156 = 698 Tk.

Explanation:

(2x-1)2÷x-5 is equal to Correct Answer 4x3 ( 2x - 1)2 ÷ x - 5 22. x - 2 ÷ 1/x5 4.x - 2 × x5 4x5 - 2 4x3

Explanation:

In a class of 78 students 14 are taking French , 22 are taking German . Of the students taking French or German , 9 are taking both courses. How many students are not enrolled in either course? Correct Answer 24 আমরা জানি, N(T) = N(A) + N(B) - N(A n B) + None None = N(T) - N (A) - N(B) + N( A n B) = 78 - 41 - 22 + 9 = 24

Explanation:

The simple interest on a sum of money will be Tk. 600 after 10 years . If the principal is trebled after 5 years , what will be the total interest at the end of the tenth year? Correct Answer Tk. 1200 ধরি, মূলধন = x টাকা x টাকায় 10 বছরের সুদ = 600টাকা x টাকায় 1 বছরের সুদ = 600/10 টাকা x টাকায় 5 বছরের সুদ = 600×5/10 = 300 টাকা যেহেতু, 5 বছরের পর মূলধন 3 গুন হয়। সুতরাং নতুন মূলধন = 3x এখন, x টাকার 5 বছরের মুনাফা = 300 টাকা 1 টাকায় 5 বছরের মুনাফা = 300/x টাকা 3x টাকায় 5 বছরের মুনাফা = 300 × 3x /x টাকা = 900 টাকা মোট মুনাফা = 900 + 300 = 1200 টাকা

Explanation:

If a + 2b = 6 and ab =4 , what is 2a+1b=? Correct Answer 3/2 2/a + 1/b 2b + a /ab = 6/4 = 3/2

Explanation:

A shopkeeper expects a gain of 22.5% on his cost price. If in a week, his sale was of TK. 392, what was his profit? Correct Answer TK.72 22.5% gain = 122.5Tk. Selling price 122.5 Tk. then profit = 22.5 Tk. Selling price 1 Tk then profit = 22.5/122.5 Tk. Selling price 392 Tk then profit = ( 22.5×392)/ 122.5 Tk. = 72 Tk.

Explanation:

A train running at the speed of 60 km/hr crosses a pole in 9 seconds. What is the length of the train? Correct Answer 150 meter 60 km = 60000 meter At 3600 second it goes = 60000 meter At 9 seconds it goes = ( 60000× 9) /3600 meter = 150 meter

Explanation:

A man spent 12 of his money and then lost 14 of the remainder . He was left with Tk. 3,600 . How much did he start with? Correct Answer Tk. 9,600 ধরি, তার মোট আয় = x টাকা তিনি মোট খরচ করেন = x/2 টাকা অবশিষ্ট টাকা = x - x/2 টাকা = x/2 টাকা হারিয়ে ফেলেন = ( x/2 × 1/4) টাকা = x/8 টাকা অবশিষ্ট টাকা = (x/2 - x/8) টাকা = 4x - x/8 = 3x/8 টাকা প্রশ্নমতে, 3x/8 = 3600 x = 3600 × 8/3 x = 9600 টাকা

Explanation:

What is the largest number that divides 84, 144 or 18 without any remainder? Correct Answer 6 84, 144 এবং 18 এর গ.সা.গু ই হবে বৃহত্তত সংখ্যা।

Explanation:

The[ triangular base of a prism is a right triangle of sides a and b = 2a . The height h of the prism is equal to 10 mm and its volume is equal to 40 mm3 , what will be the lengths of the sides a and b of the triangle ? Correct Answer 2 mm and 4 mm Bangladesh is the largest country receiving Japan's grant aid in the form of the debt relief.

Explanation:

A and B together can complete a piece of work in 12 days, B and C can do it in 20 days and C and A can do it in 15 days. A , B and C together can complete it in. Correct Answer 10 days A & B can do in 1 day = 1/12 work B & C can do in 1 day = 1/20 work C & A can do in 1 day = 1/15 work 2(A&B&C) can do in 1 day = 1/12 + 1/20 + 1/15 = 12/60 = 1/5 work. A&B&C can do in 1 day = 1/(5 × 2) = 1/10 work. Required number of days = 1/(1/10) = 10 days. Ans: D

Explanation:

A computer can perform 30 identical tasks in 6 hour. At that rate, what is the minimum number of computers that should be assigned to complete 80 of the tasks within 3 hours ? Correct Answer 6 Number of computers = (80 × 6/30 × 3) = 5.33 = minimum 6 . Ans: C

Explanation:

A student loses 1 mark for every wrong answer and scores 2 marks for every correct answer. If he answers all the 60 questions in an exam and scores 39 marks , how many of them were correct? Correct Answer 33 On 18 August 2018, former cricketer Imran Khan was sworn in as the country's 22nd prime minister.

Explanation:

There are 15 boys and 10 girls in a class. If three students are selected at random , what is the probability that 1 girl and 2 boys are selected? Correct Answer 2146 1 girl & 2 boys can be selected in = (10C1) × (15C2) ways = 10 × 105 ways = 1050 ways. 3 students can be selected from 25 students = 25C3 = 2300 ways Required probability = 1050/2300 = 21/46. Ans: C