?ABC and ?PQR are congruent
I. Area of ?ABC and ?pPQR are same
II. ?ABC and ?PQR are right angle Triangles.

If we look at statement I then we will get
If a = 3 and b = 2, a + b > 0. Here b > 0
If a = 3 and b = -2, a + b > 0. Here b < 0
Hence I alone is not sufficient.
Now if we look at Statement II only then we will get
if a = 3 and b 2, a - b > 0. Here b > 0
If a = 3 and b = -2, a - b > 0. Here b < 0
Hence II alone is not sufficient.
Now by using statements I and II together
If a = 3 and b = 2, a - b > 0 and a + b > 0. Here b > 0
If a = 3 and b = -2, a - b > 0. and a + b > 0. Here b < 0.
Hence I and II together are also insufficient.

If we look at Statement I
i = p - 17 and r = p - 103
Hence, we cannot ind how many each received so this statement is not sufficient enough.
Now by considering Statement II alone.
p + i + r = 170
Hence, we cannot find how many each received. so, this statement is not sufficient enough.
Using I sand II together, we get the value of p and the value of q and r.

If we look at Statement I
It is given that the circle are concentric. But nothing is given about their dimensions. Hence I alone is not sufficient.
In statement II ratio of area is given hence we can find the required ratio.

Let the 7 consecutive whole numbers be (n ± 3), (n ± 2), (n ± 1), n.
Now i we consider Statement I alone
Product of these 7 integers = 702800
Since 702800 = 2⁴ 5² (251)(7), it cannot be the product of 7 consecutive whole numbers. Hence I alone is insufficient.
Now if we consider Statement II alone
Given that their sum = 105 = 7n or n = 15 and then 7 consecutive integers are 12, 13, 14, 15, 16, 17, 18 So, II alone is sufficient.

Since sum is 360 hence P + Q + R + S = 360
From statement I alone we will get P = (Q + R + S)/3 from this we can find the value of P hence statement I alone is sufficient enough.
From statement II alone we can not find the value of P.

Given that their salaries are in the ratio of 3:4 and expenditure is in the ratio of 4:5 hence we can assume that salary of A and B are 3x and 4x and their expenditures are 4y and 5y.
Now we need to find the ratio of (3x - 4y)/(4x - 5y)
Consider statement I alone:
Giving of B is 25% of his salary hence his expenditure must be 75% so 3/4(4x) = 5y or 3x = 5y from this we can find the required ratio hence this statement is sufficient.
Consider statement II alone :
Given that 4x = 2000 or x = 500 but from this we can not find the value of y and hence we can not find the ratio of their savings.

Let x be the average height of the class and n be the number of students in the class.
Consider statements I alone
xn - 56 = (x + 1)(x -1)
? x + n = 57 .............(i)
Hence, the value of x cannot be found. So, I alone is not sufficient.
Consider statement I alone:
xn - 42 = (x + 1)(n - 1)
? x - n = 41 .............(ii)
Hence, the value of x cannot be found. So, II alone is not sufficient.
Both the statements together are suficient as the value of x can be found by solving (i) and (ii)

Given that Ram > Shyam, Vikram > Jay.
Hence from this we can conclude that neither Ram nor Vikram is the shortest. And we have to find the shortest. And we have to find the shortest among them:
Consider statement alone:
We know that that Ram is not the shortest, either Shyam or Jay is the shortest.
Hence (I) alone is not sufficient.
Consider statement I alone Shyam > Vikram.
From the given information and the information in (II), we get Ram > Shyam > Vikram > Jay.
Hence, (II) alone is sufficient.

Given relationship is (PQ)(RQ) = XXX
Since X can take 9 values from 1 to 9 hence we have 9 possibilities
111 = 3 x 37 444 = 12 x 37 777 = 21 x 37
222 = 6 x 37 555 = 15 x 37 888 = 24 x 37
333 = 9 x 37 666 = 18 x 18 999 = 27 x 37
But out of these 9 cases only in 999, we get the unit's digit of two numbers the same. Since it is a unique value, hence we need neither statement I nor statement II to answer the question.

Statement I alone is sufficient.
Statement II alone is not sufficient, for we can have more then one value of MN possible.