*1.A three digit number consists of 9,5 and one more number . When these digits are reversed and then subtracted from the original number the answer yielded will be consisting of the same digits arranged yet in a different order. What is the other digit?*

Sol. Let the digit unknown be n.

The given number is then 900+50+n=950+n.

When reversed the new number is 100n+50+9=59+100n.

Subtracting these two numbers we get 891-99n.

The digit can be arranged in 3 ways or 6 ways.

We have already investigated 2 of these ways.

We can now try one of the remaining 4 ways. One of these is n 95

100n+90+5=891-99n

or 199n =796

so, n=4

the unknown digit is 4.

*2.A farmer built a fence around his 17 cows,in a square shaped region.He used 27 fence poles on each side of the square. How many poles did he need altogether???*

Ans.104 poles

Sol. Here 25 poles Must be there on each side .And around four corners 4 poles will be

present. 4*25+4=100+4=104 poles.

*3.On the first test of the semester, kiran scored a 60. On the last test of the semester, kiran scored 75% By what percent did kiran's score improve?*Ans: 25%

Sol. In first test kiran got 60

In last test he got 75.

% increase in test ( 60(x+100))/100=75

0.6X+60=75

0.6X=15

X=15/0.6=25%

*4.A group consists of equal number of men and women. Of them 10% of men and 45% of women are unemployed. If a person is randomly selected from the group. Find the probability for the selected person to be an employee.*

Ans:29/40

Sol: Assume men=100,women=100 then employed men & women r (100-10)+(100-45)=145

So probability for the selected person to be an employee=145/200=29/40

*5. Randy's chain of used car dealership sold 16,400 cars in 1998. If the chain sold 15,744 cars in 1999, by what percent did the number of cars sold decrease?*

Ans: 4%

Sol. Let percentage of decrease is x , then

16400(100-x)/100=15744

16400-15744=164x

x=656/164=4%

*6. A radio when sold at a certain price gives a gain of 20%. What will be the gain percent, if sold for thrice the price?*

*A) 260%*

*B) 150%**C) 100%**D) 50%**E) None of these*Ans: 260%

Sol. Let x be original cost of the radio.

The solding price = (100+20)x=120x

If , it is sold for thrice the price ,then 3*120x=360x

So, gain percent is (360-100)=260%

*7.If the Arithmetic mean is 34 and geometric mean is 16 then what is greates number in that series of numbers?*

Ans. 64

Sol. Let two numbers be x, y;

Arthmetic mean=34=>( x+y)/2=34

x+y=68

geometric mean=16=>(xy)pow 1/2=16

xy=16*16=256

By trail and error 16*16=64*4

And 64+4/2=34

So the greatest number int hat series is 64.

*8 The diameter of the driving wheel of a bus is 140cm. How many revolutions per minute must the wheel make in order to keep a speed of 66 kmph?*

**Ans. 250**

Sol. Distance to be covered in 1 min=(66*1000)/60 m=1100m

Circumference of the wheel =(2*22/7*0.70)m=4.4m.

So, Number of revolutions per min=1100/4.4=250.

9.

*The boys and girls in a college are in the ratio 3:2. If 20% of the boys and 25% of the girls are adults, the percentage of students who are not adults is:??*

Ans.78%

Sol: Suppose boys = 3x and girls = 2x

Not adults = (80*3x/100) + (75*2x/100) = 39x/10

Required percentage = (39x/10)*(1/5x)*100 = 78%

**10 Vivek travelled 1200km by air which formed 2/5 of his trip.One third of the whole trip , he travelled by car and the rest of the journey he performed by train. The distance travelled by tain was???**

Ans.800km

Sol: Let the total trip be x km.

Then 2x/5=1200

x=1200*5/2=3000km

Distance travelled by car =1/3*3000=1000km

Journey by train =[3000-(1200+1000)]=800km.

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Posted By HasH to EveN BeforE - EveN AgaiN - EcE at 3/18/2008 06:21:00 PM

This message has been posted on HMGoogleGroup by: HASHIM CM

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