1.  A shopkeeper mixes 140 kg of P type of rice with 35 kg of Q type of rice. He then sold one – fifth of this mixture. In the remaining mixture he again mixes P and Q type of rice in the ratio 2 : 3. Now the ratio of quantity of P type of rice to that of Q type of rice in the final mixture is 3 : 1. Find that how much quantity of Q type of rice was added in the mixture?

Ans:3
After selling 1/5th of the mixture,
Amount of P type of rice remaining = 140 * (4/5) = 112 kg and amount of Q type of rice remaining = 35 * (4/5) = 28 kg
Let amount of P type and Q type of rice added is ‘2x’ and ‘3x’ respectively.
Ratio of P type of rice to Q type of rice in the final mixture-
=> (112 + 2x) : (28 + 3x) = 3 : 1 (Given)
=> (112 + 2x) = (84 + 9x)
=> x = 4
Hence quantity of Q type of rice added = 3x = 3 * 4 = 12 kg

 

2. If difference between the present ages of Ram and Kush is 22 years and 4 years hence age of Ram will be double the age of Kush, then what is the average of present ages of Ram and Kush?

Ans:4
Let present age of Kush be K years
Present age of Ram = (K +22)
As per given,
2 x (K +4) = (K +22 +4)
2K +8 = K +26
K = 18 years.
Present age of Ram = K +22 = 40 years
Required average = (40 +18)/2 =29 years.

 

3. The cost of carpeting a room 15 meters long with a carpet 60 cm wide at Rs 3.25/meter is Rs 572. What is the breadth of the room?

Ans:3
Length of the carpet =((Total cost)/(Rate/m))
= (572/3.25)m=176 m
Area of the room = Area of the carpet
= (176 X 60/100)m2=105.6 m2.
∴ Breadth of the room = (Area/15)= (105.6/15)m
= 7.04 meter = 7 meter (approx.)

 

4. If Ram and Shyam started a company by investing Rs.20000 and Rs.50000, as Ram is an active partner he invests additional Rs.40000 from the part of his salary and Rajiv joined them after 6 months and he invests Rs.60000, then what is the ratio of investments of Ram, Shyam and Rajiv after 1 year?

Ans:2
Total investment of Ram = (20000 +40000) x 12 = 60000 x 12
Total investment of Shyam = (50000) x 12
Total investment of Rajiv= 60000 x 6
Ratio of investments of Ram, Shyam and Rajiv after 1 year
= (60000 x 12): (50000 x 12): (60000 x6)
= 6:5:3.

 

5. When price of wheat increased by 44%, a family reduced its consumption in such a way that the expenditure on wheat is only 20% more than before. If 60 kg of wheat was the previous consumption. Find the decrease in the consumption.

Ans:3
Let the price 1 kg wheat = x Rs.
Let y kg be the present consumption of wheat
1.20 [60x] = 1.44 (x)(y).
Y = (1.20*60/1.44) = (72/1.44) ϸ Y = 50 kg
Consumption is decreased by 60-50 = 10 kg
Hence 3

 

6. In an election Samiksha got 45 votes less than Meenakshi. Meenakshi got 65 votes more than Meera. Sudhanshu got 1740 votes which is 35 votes more than Meera. Radhika got votes which are 6500 less than total votes voted in election. Calculate the approximate percent of votes Radhika got in the election if she got 75 votes more than Samiksha?

Ans:1
Votes received by Sudhanshu = 1740
Votes received by Meera = 1740 – 35 = 1705
Votes received by Meenakshi = 1705 + 65 = 1770
Votes received by Samiksha = 1770 – 45 = 1725
Votes received by Radhika = 1725 + 75 = 1800
Total votes voted in election = 1800 + 6500 = 8300
Therefore, approximate percent of votes received by Radhika = 1800/8300 * 100= 21.69% (approx.)

 

7.If Raman borrowed some amount at the rate of 15% per annum on SI charged after every 4 months and in 44 months he pays total interest of Rs.16500, then how much amount Raman borrowed?

Ans:2
Let amount borrowed by Raman be P.Interest is charged after every 4 months, so number of terms = (44/4) = 11

Rate of interest for 4 months = (4/12) x 15 = 5%

Total interest = 11 x (5/100) x (P) = 16500

P= (16500) x (20/11) = 1500 x 20 = Rs.30000

 

8. Sunaina sold an article to Samir at a profit of 10%, Samir sold that article to Sujal at a profit of 12%, Sujal sold that article to Sanjana at a loss of 20%. Sanjana again sold that article to Sunaina at a profit of 5%. Find the overall percentage profit/loss for Sunaina?

Ans:3
Let the initial cost price of the article for Sunaina = Rs.100
Cost price for Samir = 100 x 110/100
Cost price for Sujal = 100 x 110/100 x 112/100
Cost price for Sanjana = 100 x 110/100 x 112/100 x 80/100
Cost price for Sunaina = 100 x 110/100 x 112/100 x 80/100 x 105/100 = Rs.103.488
Selling price of the article for Sunaina = 110 ( sunaina sold to samir at 10% profit)
% profit for Sunaina = (110 – 103.488)/103.488 x 100 = 6.29%

 

9. If upstream time taken by a boat to cover certain distance is 100% more than the downstream time taken by the boat to cover same distance, then speed of stream is what percent of the speed of boat in still water?

Ans:1
Let speed of boat in still water is A km/h and speed of stream be B km/h.
As upstream time is 100% more than downstream time, so upstream speed is half of the downstream speed.
2 x(A-B) = A +B
2A -2B = A +B
A = 3B
B = (1/3) x A = 33.33% of A

 

10. A and B are suppose to do a work. A when working alone takes 4 hrs more while B when working alone takes 9 hrs more than the time taken when they are working together. How long will they take to complete the work when they are working together?

Ans:3
Let the time taken by them to complete the work when working together be X hrs
Then time taken by A alone = (X + 4) hrs
And time taken by B alone = (X + 9) hrs
together they will work as
(1/(X + 4)) + (1/(X + 9)) = 1/X
Solving this, we get X = 6hrs

 

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