Mathmetics
ISBT Mathmetics for all banking PO,Clerk,IBPS PO,Railway,SSC,IAS,OAS Exams
Q1. | The sum of the squares of two positive integers is 208. If the square of the larger number is 18 times the smaller number, then what would be the difference of the larger and smaller numbers ? |
1) | 2 | 2) | 3 |
3) | 4 | 4) | 6 |
5) | None of these |
Answer : 4
Explanation : Let, the larger and smaller numbers are x and y respectively.
Explanation : Let, the larger and smaller numbers are x and y respectively.
x2 + y2 = 208 --------- (i)
x2 = 18y
or x2 - 18y = 0 -------- (ii)
Equating from both equation,we get
y2 +18y - 208 = 0
or y2 + 26y - 8y - 208 = 0
or y (y+26) - 8 (y + 26) = 0
or y = 8 so, x = 12
Therefore, x-y = 12 - 8 = 4

Q2. | What is the remainder when 135+145 + 155 + 165 is divided by 29 ? |
1) | 0 | 2) | 3 |
3) | 5 | 4) | 8 |
5) | None of these |
Answer : 0

Q3. | What should be the remainder when 2 100 is divided by 101 ? |
1) | 1 | 2) | 11 |
3) | 99 | 4) | 100 |
5) | None of these |
Answer : 99

Q4. |
|
1) | 3 | 2) | 5 |
3) | 9 | 4) | 11 |
5) | None of these |
Answer : 11
Explanation :
Explanation :
Let, the ten's digit be x and unit's digit be y.
Then, number = 10x + y.
Number obtained by interchanging the digits = 10y + x.
(10x + y) + (10y + x) = 11(x + y), which is divisible by 11.

Q5. |
|
1) | 184 | 2) | 192 |
3) | 196 | 4) | 212 |
5) | None of these |
Answer : 192
Explanation :
Explanation :
(x + y)2 = (x - y)2 + 4xy
or x + y = 28, x - y = 4
or 4xy = (28)2 - (4)2
or 4xy = (28 + 4) (28 - 4)
or xy = = 32 x 6 = 192

Q6. |
|
1) | (2^16 + 1) | 2) | (2^16 - 1) |
3) | (7 x 2^23) | 4) | (2^96 + 1) |
5) | None of these |
Answer : (2^96 + 1)
Explanation :
Explanation :
Let, 232 = x. Then, (232 + 1) = (x + 1).
Let, (x + 1) be completely divisible by the natural number N.
Then, (296 + 1) = [(232)3 + 1] = (x3 + 1) = (x + 1)(x2 - x + 1), which is completely divisible by N, since (x + 1) is divisible by N.

Q7. | Two-fifth of a number is two more than one-third another number.If the sum of the two numbers is 16,what is their product ? |
1) | 40 | 2) | 48 |
3) | 54 | 4) | 60 |
5) | None of these |
Answer : 60
Explanation : Let, two numbers are x and y respectively.
Explanation : Let, two numbers are x and y respectively.
According to the questions, x + y = 16 ------- (I) and 2x/5 - y/3 = 2 -------- (II)
or 6x -5y = 30
Solving both equations , we get x = 10 and y = 6
So, their product = 10 X 6 = 60

Q8. |
|
1) | 2825 | 2) | 2975 |
3) | 3025 | 4) | 3775 |
5) | None of these |
Answer : 3775
Explanation :
Explanation :
We know that,Sn = (1 + 2 + 3 + ... + 50 + 51 + 52 + ... + 100)/2 - (1 + 2 + 3 + ... + 50)/2
= 100 x (1 + 100) - 50 x (1 + 50) = (50 x 101) - (25 x 51)
= (5050 - 1275) = 3775.

Q9. |
|
1) | 8 | 2) | 9 |
3) | 10 | 4) | 12 |
5) | None of these |
Answer : 10
Explanation :
Explanation :
4 a 3 |
9 8 4 } ==> a + 8 = b ==> b - a = 8
13 b 7 |
Also, 13 b7 is divisible by 11 (7 + 3) - (b + 1) = (9 - b)
(9 - b) = 0
or b = 9 (b = 9 and a = 1)
So, (a + b) = 10.

Q10. |
|
1) | 1 | 2) | 2 |
3) | 3 | 4) | 4 |
5) | None of these |
Answer : 4
Explanation :
Explanation :
We, know that , Dividend = (divisor x Quotient )+Reminder
D = 5Q + 3
or D2 = (5Q + 3)2 = (25Q2 + 30Q + 9) = 5(5Q2 + 6Q + 1) + 4
On dividing D2 by 5, we get 4 as remainder.
