২২৯৪১
In a city 40% of the people have black hair, 25% have black eyes and 10% have both black hair and black eyes. What percentage of the people in the city has neither black hair nor black eyes?
উত্তর
45
সমাধান
Percentage of people having atleast one of the qualities = 40% + 25% - 10% = 55%
Percentage of people having neither of the qualities = 100% - 55% = 45%
২২৯৪২
A football team plays 154 games in a year. If till July the team has won 40 and lost 20 games , how many of the remaining games the team must win to finish the year winning nearly 50% of the games?
উত্তর
37
সমাধান
50% of the games = 50% of 154 = 50/100×154 = 77
Number of games the team must win = 77 - 40 = 37
২২৯৪৩
A merchant sells a radio for Tk. 80 and thereby makes a profit of 25% of the cost. What is the ratio of cost to selling price?
উত্তর
4/5
সমাধান
at 25% profit, if cost price = 100, then sell price = 125
now, if sell price = 80, then cost price = (100*80)/125 = 64
so ratio = 64/80 = 4:5
২২৯৪৪
A sum of Taka 3000 invested at 4% per annum for a number of years earned Taka 300 interest. What is the time period?
উত্তর
2.5 years
সমাধান
We know, Interest, I = P n r
Now, 3000×n×4/100 = 300
or, n = 300×100/(3000×4) = 2.5 years
২২৯৪৫
Mr. Mamun bought 73 rolls of film. He can take 24 pictures with each roll of film. What is the total number of pictures he can take with 73 rolls of film?
উত্তর
1,752
সমাধান
1 roll contain = 24 pictures73 rolls contain = 73*24 = 1,752 pictures (Ans.)
২২৯৪৬
Two students appeared at an examination. One of them secured 9 marks more than the other and his marks was 56% of the sum of their marks. The marks obtained by them are:
উত্তর
42, 33
সমাধান
Another students got = 100% - 56% = 44% of their total marks
Difference = 56% - 44% = 12%
12% of the sum = 9 marks
So, 100% of the sum = 9×100/12 = 75 marks
So, one students got = 56% of 75 = 56/100×75 = 42 marks
Then the other student got = 75 - 42 = 33 marks
২২৯৪৭
Saif charges TK. 5.00 for every hour he works. Last week he worked for 8 hours. He spent TK. 12.00 of the money he earned. which expression could be used to find how much money he had left?
উত্তর
TK.5.00×8-TK.12.00
সমাধান
remaining money = total money that he earned - money that he spent = Tk 5.00*8 - Tk 12.00
২২৯৪৮
A class of 50 girls and 70 boys sponsored a party. If 40% of the girls and 50% of the boys attended the party, approximately what percent of the class attended?
উত্তর
46
সমাধান
First, we need to find out 40% of the 50 girls. That is 50 x 0.4 = 20 girls.
Next, we need to find out 50% of the 70 boys. That is 70 x 0.5 = 35 boys.
Therefore, 20 + 35 = 55 people attended.
In total there were 50 + 70 = 120 people.
So the percent would be 55/120 = 11/24 ≈ 45.83% ≈ 46%.
২২৯৪৯
The price of a certain television set is discounted by 10 percent, and the reduced price is then discounted by 10 percent. The series of successive discount is equivalent to a single discount of-
উত্তর
19
সমাধান
Let the price of the TV set be S.
Price after 10% discount = S - 10% of S = 0.9S
Price after another 10% successive discount = 0.9 - 10% of 0.9S = 0.09S = 0.81S
Actual discount = (S - 0.81S)/S×100% = 19%
২২৯৫০
A sales representative will receive a 15% commission on a sale of Tk. 28,000. If she has already received Tk. 1500 as an advance of that commission, how much more is due on the commission?
উত্তর
Tk. 2700
সমাধান
15% of 28000 Tk = (28000*15/100) = 4200Tk
As she received 1500 Tk Commission already, so she will receive more(4200 - 1500) = 2700 Tk