UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 21

EASY

UPSC CDS

IMPORTANT

Earn 100

$a, b, c, d$ are non-zero integers such that $(a b)$ divides $(c d)$ . If $a$ and $c$ are coprime, then which one of the following is correct?

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Important Questions on UPSC CDS (II) Previous Year Paper 2017

MEDIUM

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 22

If the roots of the equation

a (b - c) x^{2} + b (c - a) + c (a - b) = 0

are equal, then which one of the following is correct?

EASY

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 23

The non-zero solution of the equation

\frac{a - x^{2}}{b x} - \frac{b - x}{c} = \frac{c - x}{b} - \frac{b - x^{2}}{c x}

, where

b \neq 0, c \neq 0

is

MEDIUM

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 24

If

k

is an integer, then

x^{2} + 7 x - 14 (k^{2} - \frac{7}{8}) = 0

has

EASY

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 25

How many numbers between

500

and

1000

are divisible by

13

?

EASY

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 26

To maintain

8

cows for

60 d a y s

, the milk man has to spend

₹ 6, 400

. To maintain

5 c o w s

for

n d a y s

, he has to spend

₹ 4, 800 .

What is the value of

n

?

EASY

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 27

A student has to secure

40 % o f m a r k s

to pass an examination. He gets only

45 m a r k s

and fails by

5 m a r k s

. The maximum marks are:

EASY

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 28

What is the value of

u

in the system of equations

3 (2 u + v) = 7 u v, 3 (u + 3 v) = 11 u v

?

EASY

UPSC CDS

IMPORTANT

UPSC CDS Previous Year Papers>Chapter 2 - UPSC CDS (II) Previous Year Paper 2017>Elementary Mathematics>Q 29

Five years ago, Ram was three times as old as Shyam. Four years from now, Ram will be only twice as old as Shyam. What is the present age of Ram?