1. While calculating the edge of a square, a worker makes an error of 2% in excess. What % error does he make in calculating area? (%)
A. 4.04
B. 4
C. 40.4
D. 4.004
Answer: Option A
Explanation:
Given Error = 2% while measuring the side of a square.
If the correct value of the side of the square is 100, the measured value:
=> 100 + 2% *100
= 100+2=102
The area of a square with edge 100 = side*side
=> 100*100
=> 10000
The area of a square with side 102 = 102*102= 10404
Error in area calculation = 10404-1000 = 404
% error= [latex]\frac{404}{10000 }[/latex]*100
= 4.04%
2. Akash and Akshay are business partners. Akash invests Rs 35,000 for a period of 8 months and Akshay invests Rs 42,000 for a period of 10 months. Out of a total profit of Rs 31,570 what is Akash’s share?
A. Rs 12,420
B. Rs 18,040
C. Rs 18,942
D. Rs 12,628
Answer: Option D
Explanation:
For a given business profit is directly dependent upon the capital invested and the time of investment.
=> Ratio of shares of Akash and Akshay becomes: (35,000*8)/(42,000*10) = [latex]\frac{2}{3 }[/latex]
=>% of profit belonging to Akash: [latex]\frac{2}{3 + 2 }[/latex]*(31,570)
=>Rs 12,768
3. In what ratio must one add water to milk so as to gain 16.666% on the selling this mixture at the cost price?
A. 1:6
B. 1:3
C. 6:1
D. 3:1
Answer: Option A
Explanation:
To start off this question let us assume that cost price of 1 litre milk is Rs 1
No need to make a mixture and sell this mixture at 1 Rs per liter such that the total gain on the mixture is 16.667%.
Therefore, CP of 1 liter of the mixture becomes (quantity of milk)/ (quantity of mixture containing 1 L milk)*(the price of 1-liter milk).
=>[latex]\frac{(100}{(100+50/3) }[/latex]*1
=>CP of 1-litre milk of mixture: Rs [latex]\frac{5}{6 }[/latex]
As the price of any amount of water is zero, and as 1-liter milk costs Rs 1.5/6litre of the mixture will comprise entirely of cost of milk which means,1 liter of the mixture will
contain 5/6th amount of milk.
=>Water is added in the ratio of (1-[latex]\frac{5}{6 }[/latex])= [latex]\frac{1}{6 }[/latex]
4. Ram can finish a puzzle in 3 hours and Shyam can do the same in 2 hours. Both of them finish the puzzle and get 15 candies. What is Ram’s share?
Answer: Option B
Explanation:
The question is based on efficiency to do work.
Ram can finish a puzzle in 3 hours. Shyam can finish the puzzle in 2 hours.
=>In one hour Ram can finish 1/3rd of a puzzle
=>In one hour Shyam can finish half the puzzle
A total of 15 candies are to be shared amongst both of them
Hence Ram’s share must be = ((Work done by Ram in 1 hour)/(Work is done by Shyam in one hour)+(Work done by Ram in an hour))*15
=> 1/3/((1/2)+(1/3))*15
=> (1/3/(5/6))*15
=> [latex]\frac{6}{15 }[/latex]*(15)
=>6 candies
5. A man sells 45 lemons for Rs 40 and loses 20%. At how much price should he sell 24 lemons to the next customer to make a 20% profit?
Answer: Option A
Explanation:
Let cost price of lemons be x.
Selling price of lemons becomes CP - loss.
=>SP=x-(20/100)x
=>40=x(80/100)
=>50
So 45 lemons cost Rs 50
Cost of 1 lemon = [latex]\frac{50}{45 }[/latex] Rs
Cost of 24 lemons = ([latex]\frac{50}{45}[/latex])*24 =80/3 Rs
Selling Price of 24 lemons = ([latex]\frac{80}{3 }[/latex])+([latex]\frac{20}{100 }[/latex])([latex]\frac{80}{3 }[/latex])=Rs 32