প্রশ্নঃ A man can cross 10 miles distance of a river in favor of the stream in 2 hours . He can come back against the stream along the same way in 5 hours . What is the average speed, in miles per hour, for the entire trip ?
Total distance = 10 + 10 = 20 miles
Total time required = 5 + 2 = 7 hours
Average speed = 20/7 miles per hour
প্রশ্নঃ On a trip of 200 miles, a man travels at the rate of 40 miles per hour for the first 100 miles. For the rest of the trip, he travels at the rate of 55 miles per hour . What is his average speed, in miles per hour, for the total trip ?
Total time spent = 100/40 + 100/55 = 5/2 + 20/11 = 95/22 hours
Average speed = 200 / (95/22) = 200 x 22 / 95 = 880/19 miles per hour
প্রশ্নঃ An item is sold for $65.00, giving the retailer a profit of 30% of the cost . What will be the new retail price if the retailer cuts his profit to 10% of costs ?
when sp 130 then cp 100
when sp 1 then cp. 100/130
When Sp 65 then cp 100×65/130
So Cp =50
Therefore the new retail price = 50+50×10%= $55
প্রশ্নঃ Six consecutive whole numbers are given ; the sum of the first three numbers is 27. What is the sum of the last three numbers ?
Let the numbers be (x-3), (x-2), (x-1), x, (x+1), (x+2) respectively.
Now, (x-3) + (x-2) + (x-1) = 27
or, 3x - 6 = 27
or, 3x = 33
or, x = 11.
So, x + (x+1) + (x+2) = 11 + 12 + 13 = 36.
decreased by 20%
increased by 4%
decreased by 2%
প্রশ্নঃ The length of rectangle is increased by 20% and the width is decreased by 20% . What is the percentage increase or decrease of the area of the rectangle .
We can let L= the original length
and W= the original width
Thus, the original area of the rectangular is LW and the new area is 1.2L× 0.8W= 0.96LW
So, the area is decreased by 4%
প্রশ্নঃ A arden is 60m long and 20m wide. Inside the garden there is a 5m wide path around it . The area of the path is in square meter .
Area including path = 60 x 20 = 1200 sq. m.
Length without path = 60 - (5x2) = 50 m
Width without path = 20 - (5x2) = 10 m
Area without path = 50 x 10 = 500 sq. m.
Area of the path = 1200 - 500 = 700 sq. m.
প্রশ্নঃ A man binds 112 books in a day , and his assistant work 1/4 as fast . How many days will it take them to bind 560 books, if each alone works on alternate days ?
His assistant binds 1/4 x 112 = 28 books a day.
So, they bind 112 + 28 = 140 books in every 2 days working in alternate days
They will need 560/140 x 2 days = 8 days.
প্রশ্নঃ First Atom Bomb was dropped in
The United States detonated two nuclear weapons over the Japanese cities of Hiroshima and Nagasaki on August 6 and 9, 1945, respectively. The two bombings killed between 129,000 and 226,000 people, most of whom were civilians, and remain the only use of nuclear weapons in armed conflict
প্রশ্নঃ Sania Mirza is a
Sania born 15 November 1986) is an Indian professional tennis player. A former doubles world No. 1, she has won six Grand Slam titles in her career. From 2003 until her retirement from singles in 2013, she was ranked by the Women's Tennis Association as India's No. 1 player. Throughout her career, Mirza has established herself as by far the most successful Indian female tennis player ever and one of the highest-paid and most high-profile athletes in the country.
U. N. Body
International Financial Institution
প্রশ্নঃ The World Bank is a
The World Bank is an international financial institution that provides loans and grants to the governments of low- and middle-income countries for the purpose of pursuing capital projects. It comprises two institutions: the International Bank for Reconstruction and Development (IBRD), and the International Development Association (IDA). The World Bank is a component of the World Bank Group.
Used Injection syringe
Asexual physical contact
Polluted drinking water
প্রশ্নঃ Which of the following is not a part of milk ?
Milk is a nutrient-rich liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals, including breastfed human infants before they are able to digest solid food.
Early-lactation milk is called colostrum, which contains antibodies that strengthen the immune system and thus reduces the risk of many diseases.
It holds many other nutrients, including protein and lactose. Interspecies consumption of milk is not uncommon, particularly among humans, many of whom consume the milk of other mammals.
When the earth comes in between the moon and the sun
When the sun comes between the earth and the moon
When the moon comes between the earth and the sun
When the mars comes between the sun and the moon
প্রশ্নঃ Phulbari Coal Mine is in
The Phulbari coal project is a proposed open pit coal mine in northwest Bangladesh and includes the construction of at least one 500-MW power plant. At full production about eight million tons of coal will be transported by rail and barges to an offshore reloading facility located in Akram Point.
প্রশ্নঃ Paharpur Monastery is in
Geographically located to the north-west of Bangladesh in the district of Naogaon, the heart-land of ancient “Varendra”, close to the village of Paharpur the extensive ruins of the Buddhist monastic complex are the most spectacular and important pre-Islamic monument in Bangladesh.