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Q1. x=25(a^2) -25(b^2) and Y=[5(a-b)]^2 then
A. X=Y
B. X<Y
C. X>Y
D. None
Q2.. if a+b=3(c+d) which of the following is average of a,b,c,d
A. c+d
B.(c+d)\4
C. 3(c+d)\8
D. 3(c+d)\4
Q3.. if 7x+3y=17 and 3x+7y=19 , WHat is arithmetic mean of x and y???
A. 1.55
B. 1.8
C. 3.6
D. 36
Q.4 when a>b then (a^3)-(b^3) is greater than
A. zero
B.. (a+b)^3
C. (a-b)^3
D. none
Q5.. Rule to Add two scalar is Head to TAil rule or right hand rule or simple addition"??
Malik
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hi
Q1. D is not a possible answer as one of the other three must be true.
I tried this:
Now subtract:
If a = b then X = Y
If b>0 and b>a then 50b(b-a) > 0 then Y > X etc etc
So the answer seems to depend on the values of a and b.
Should answer D read "It is not possible to decide."
Q2. Try simplifying (a+b+c+d)/4
Q3. You could try solving for x and y, but a quicker method is to add the equations and re-arrange to find (x+y)/2
Q4. I think this also depends on the values of a and b. I need to spend more time on it so I'll come back to this question later.
LATER EDIT:
You can make a deduction from this if you know more about a and b such as a, b > 0 and b>a
Did you get told this at the start of these questions? It's important to have the whole question.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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Plz decide only one option in question 1 I also know that option d is incorrect
Suppose if option d is
D. Not sure then ans d is correct
Last edited by Zeeshan 01 (2017-07-17 22:08:52)
Malik
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You can also try one more formula for
It isPractice makes a man perfect.
There is no substitute to hard work
All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam
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Hehe I know all these formulas
Malik
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Q1. D is not a possible answer as one of the other three must be true.
I tried this:Now subtract:
Why u subtract???
Malik
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A. X=Y
B. X<Y
C. X>Y
If you calculate Y - X and the answer is:
zero ............. means Y = X
positive .........means Y > X
negative ........means X > Y
So subtracting was a quick way to help decide between the alternatives.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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??
Malik
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Arithmetic mean formula is A=(x+y)\2
Malik
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Can you Clearify Question 2,3,4???
Malik
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Q2. The average is (a + b + c + d)/4
If you start with this and use the given information to eliminate a and b it is a short work to get one of the possible answers.
Q3. Add the equations together : 10x + 10y = 36
It is a short step to get (x+y)/2
Q4. Depending on what values I choose for a and b I get many possible answers:
If a=1.1 and b=1, then answers A and C are TRUE.
If a=-2 and b=-3, then answers A,B and C are all TRUE.
If a=1 and b=0, then answer A is TRUE.
I'll leave it to you to try to find a case where only D is TRUE.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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Okk!,, it takes long time
Malik
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