19 Search

Q:

3x + y = 19 and x + 3y = 1. Find the value of 2x + 2y

A) 20	B) 18
C) 11	D) 10

Answer & Explanation Answer: D) 10

Explanation:

To solve a pair of simultaneous equations such as those given we can add or subtract them.

Adding we get 4x + 4y = 20

Therefore 2x + 2y = 10

Report Error

View Answer Report Error Discuss

Filed Under: Numbers
Exam Prep: GRE

Q:

If $a^{2} = 12, t h e n a^{4} = ?$

A) 144	B) 72
C) 36	D) 24

Answer & Explanation Answer: A) 144

Explanation:

Given a x a = 12

asked to find a x a x a x a = (a x a) x (a x a)

a⁴ = a² x a²

= 12 x 12

= 144.

More :: Mathematical operations questions and answers.

Report Error

View Answer Report Error Discuss

Filed Under: Numbers
Exam Prep: Bank Exams , AIEEE , CAT , GATE
Job Role: Bank Clerk , Analyst , Bank PO , IT Trainer

Q:

If the length of the diagonal of a square is 20cm,then its perimeter must be

a. $40 \sqrt{2}$ cm b. $30 \sqrt{2}$ cm c. 10cm d. 15 $\sqrt{2}$ cm

A) a	B) b
C) c	D) d

Answer & Explanation Answer: A) a

Explanation:

We know that d=√2s

Given diagonal = 20 cm

=> s = 20/ $\sqrt{2}$ cm

Therefore, perimeter of the square is 4s = 4 x 20/ $\sqrt{2}$ = 40 $\sqrt{2}$ cm.

Report Error

View Answer Report Error Discuss

Filed Under: Area
Exam Prep: Bank Exams
Job Role: Bank PO

Q:

If $\log_{x} (\frac{9}{16}) = - \frac{1}{2}, t h e n t h e v a l u e o f x ?$

A) -3/4	B) 3/4
C) 81/256	D) 256/81

Answer & Explanation Answer: D) 256/81

Explanation:

Report Error

View Answer Report Error Discuss

Filed Under: Logarithms
Exam Prep: Bank Exams
Job Role: Bank PO

Q:

Wheels of diameters 7cm and 14cm start rolling simultaneously from x & y which are 1980 cm apart towards each other in opposite directions. Both of them make the same number of revolutions per second. If both of them meet after 10seconds.The speed of the smaller wheel is

A) 22m/s	B) 33m/s
C) 44m/s	D) 55m/s

Answer & Explanation Answer: A) 22m/s

Explanation:

let each wheel make x revolutions per sec. Then $[(2 π * \frac{7}{2} * x) + (2 π * 7 * x)] * 10 = 1980$ $(2 * \frac{22}{7} * \frac{7}{2} * x) + (2 * \frac{22}{7} * \frac{7}{2} * x) = 198$

$66 x = 198$

distance moved by smaller wheel in 3 revolutions

= $2 * \frac{22}{7} * \frac{7}{2} * 3 = 66 c m$

speed of smaller wheel = $\frac{66}{3}$ m/s = 22m/s

Report Error

View Answer Report Error Discuss

Filed Under: Area
Exam Prep: Bank Exams
Job Role: Bank PO

Q:

Who was the first recipient of a scholarship offered by the Indian Society of Oriental Arts in 1907

Answer

Nandala Bose

Workspace

Report Error

View answer Workspace Report Error Discuss

Subject: Indian Culture

Q:

A sector of 120, cut out from a circle, has an area of $\frac{66}{7} c m^{2}$ . Find the radius of the circle ?

A) 1	B) 2
C) 3	D) 4

Answer & Explanation Answer: C) 3

Explanation:

Let the radius of the circle be r cm. Then,

$\frac{120}{360} {πr}^{2} = \frac{66}{7}$

$r^{2} = \frac{66}{7} * \frac{7}{22} * 3$

r=3.

Report Error

View Answer Report Error Discuss

Filed Under: Area
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Bank Clerk , Bank PO

Q:

Two concentric circles form a ring. The inner and outer circumferences of ring are $\frac{518}{7}$ m and $\frac{352}{7}$ m respectively. Find the width of the ring.

A) 4	B) 5
C) 6	D) 7

Answer & Explanation Answer: A) 4

Explanation:

Let the inner and outer radii be r and R metres.

Then $2 πR = \frac{352}{7} = > R = \frac{352}{7} * \frac{7}{22} * \frac{1}{2} = 8 m$

$2 πR = \frac{528}{7} = > R = \frac{528}{7} * \frac{7}{22} * \frac{1}{2} = 12 m$

=> Width of the ring = (R - r) = (12 - 8) m = 4 m.

Report Error

View Answer Report Error Discuss

Filed Under: Area
Exam Prep: AIEEE , Bank Exams , CAT
Job Role: Bank Clerk , Bank PO

Searching for "19"

Quick Links