২২৪৮১
If the co-ordinates of A and B are (4, 1) and (-2, 7) respectively, then the co-ordinates of the midpoint of AB are.
উত্তর
(1, 4)
সমাধান
Let the midpoint coordinate of AB be (x, y).
Now, x = (x1 + x2)/2 = (4 + ( - 2))/2 = 2/2 = 1
And, y = (y1 + y2)/2 = (1 + 7)/2 = 8/2 = 4
So, the coordinate (x, y) = (1, 4).
২২৪৮২
In a class , the ratio of the number of boys to girls is 5: 3. What percent of the students of the class are girls?
উত্তর
37.5%
সমাধান
Summation of ratios = 5 + 3 = 8
So, percentage of girls = 3 / 8 x 100% = 37.5%
২২৪৮৩
If one cake serves 7 People, How many cakes are needed to serve a party of 98 people?
উত্তর
14
সমাধান
If 7 people need to be served 1 cake
Then, 98 people need to be served = 98/7 = 14 cakes
২২৪৮৪
A car travels at the rate of 50 miles per hour. How many minutes will it take to travel 2/5 miles at this speed?
উত্তর
0.48
সমাধান
The car can travells 50 miles in an hour or 60 minutes
So, the car can travells 2/5 miles in 60 x (2/5) / 50 minutes = 0.48 minutes
২২৪৮৫
A jar contains 10 red marbles and 30 green marbles. How many red marbles must be added to the jar so that 60% of the marbles will be red?
উত্তর
35
সমাধান
New percentage of green marbles = 100% - 60% = 40%
Now, 40% of total marbles = 30 [number of green marbles remains unchanged]
So, total number or 100% of marbles = 30 x 100 / 40 = 75
More red marbles required = 75 - (10 + 30) = 35
২২৪৮৬
How long would it take a man cycling at 30 miles per hour to cover a distance of 44 feet?
উত্তর
1 sec
২২৪৮৭
Karim drove for h hours at a constant rate of r miles per hour. How many miles did he go during the final 20 minutes of his drive?
উত্তর
r/3
সমাধান
we know,
Distance (D) = Speed (S) * Time (T)so, S * T = r*20/60 mins
= r / 3.(ans)
২২৪৮৮
A man deposits Tk 600 in a Bank at 10% interest rate compounded annually, At the end of the second year, the total amount including interest will become Tk-
উত্তর
726
সমাধান
C = P(1 + r/n)nt [C = principal with interest, r = rate of interest, n = number of times interest is compounded per time period, t = number of time periods]
Now, P = 600, r = 10/100 = 0.1, n = 1, t = 2
So, C = 600 x (1 + 0.1)2 = 600 x 1.12 = 600 x 1.21 = 726 TK
২২৪৮৯
What is the are a of a square (in sq. meter) if its perimeter is 40 meter?
উত্তর
100
সমাধান
Side of the square = 40 / 4 = 10 m [ Perimeter of square = 4 x side length]
So, area of the square = 102 = 100 m2
২২৪৯০
What is the total, interest on Tk 800 at 12.5% per annum for 9 months (in taka)?
উত্তর
75
সমাধান
১২.৫% সুদে ৮০০ টাকার এক বছরের সুদ=৮০০×(১২৫/১০০×১০)=১০০ টাকা১২ মাসের সুদ ১০০ টাকা১ মাসের সুদ =(১০০/১২)৯ মাসের সুদ =(১০০*৯)/১২=৭৫ টাকা