If ax = by, then:

Byadmin July 18, 2022

Question:
If ax = by, then:

[A].

log	a	=	x
	b		y

[B].

log a	=	x
log b	=	y

[C].

log a	=	y
log b	=	x

[D].

None of these

Answer: Option C

Explanation:

ax = by

log ax = log by

x log a = y log b

	log a	=	y	.
	log b		x

Aptitude | Simple Interest

What will be the ratio of simple interest earned by certain amount at the same rate of interest for 6 years and that for 9 years?

Question: What will be the ratio of simple interest earned by certain amount at the same rate of interest for 6 years and that for 9 years?
[A].

1 : 3
[B].
1 : 4
[C].
2 : 3
[D].
Data inadequate

Answer: Option C

Explanation:

Let the principal be P and rate of interest be R%.

Required ratio =

P x R x 6

100

= 6PR = 6 = 2 : 3.

P x R x 9

100

9PR 9

Video Explanation: https://youtu.be/GaaEDwTWc6w

Read More What will be the ratio of simple interest earned by certain amount at the same rate of interest for 6 years and that for 9 years?
Aptitude | Time And Work

A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in :

Question: A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in :
[A].

4 days
[B].
6 days
[C].
8 days
[D].
12 days

Answer: Option C

Explanation:

(A + B + C)’s 1 day’s work = 1 ;

6

(A + B)’s 1 day’s work = 1 ;

8

(B + C)’s 1 day’s work = 1 .

12

(A + C)’s 1 day’s work

= 2 x 1 – 1 + 1

6 8 12

= 1 – 5

3 24

= 3

24

= 1 .

8

So, A and C together will do the work in 8 days.

Read More A and B can do a work in 8 days, B and C can do the same work in 12 days. A, B and C together can finish it in 6 days. A and C together will do it in :

Aptitude | Permutation And Combination

In a group of 6 boys and 4 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be there?

Question: In a group of 6 boys and 4 girls, four children are to be selected. In how many different ways can they be selected such that at least one boy should be there?
[A].

159

[B].

194

[C].

205

[D].

209

Answer: Option D

Explanation:

We may have (1 boy and 3 girls) or (2 boys and 2 girls) or (3 boys and 1 girl) or (4 boys).

Required number
of ways

= (6C1 x 4C3) + (6C2 x 4C2) + (6C3 x 4C1) + (6C4)

= (6C1 x 4C1) + (6C2 x 4C2) + (6C3 x 4C1) + (6C2)

= (6 x 4) +

6 x 5

4 x 3

6 x 5 x 4

x 4

6 x 5

2 x 1

3 x 2 x 1

2 x 1

= (24 + 90 + 80 + 15)

= 209.

Aptitude | Time And Distance

It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the cars is:

Question:
It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the cars is:

[A].

2 : 3
[B].
3 : 2
[C].
3 : 4
[D].
4 : 3

Answer: Option C

Explanation:

Let the speed of the train be x km/hr and that of the car be y km/hr.

Then, 120 + 480 = 8 1 + 4 = 1 ….(i)

x y x y 15

And, 200 + 400 = 25 1 + 2 = 1 ….(ii)

x y 3 x y 24

Solving (i) and (ii), we get: x = 60 and y = 80.

Ratio of speeds = 60 : 80 = 3 : 4.

Read More It takes eight hours for a 600 km journey, if 120 km is done by train and the rest by car. It takes 20 minutes more, if 200 km is done by train and the rest by car. The ratio of the speed of the train to that of the cars is:
Aptitude | Height And Distance

A man standing at a point P is watching the top of a tower, which makes an angle of elevation of 30° with the man’s eye. The man walks some distance towards the tower to watch its top and the angle of the elevation becomes 60°. What is the distance between the base of the tower and the point P?

Question: A man standing at a point P is watching the top of a tower, which makes an angle of elevation of 30° with the man’s eye. The man walks some distance towards the tower to watch its top and the angle of the elevation becomes 60°. What is the distance between the base of the tower and the point P?
[A].

43 units
[B].
8 units
[C].
12 units
[D].
Data inadequate

Answer: Option D

Explanation:

One of AB, AD and CD must have given.

So, the data is inadequate.

Read More A man standing at a point P is watching the top of a tower, which makes an angle of elevation of 30° with the man’s eye. The man walks some distance towards the tower to watch its top and the angle of the elevation becomes 60°. What is the distance between the base of the tower and the point P?
Aptitude | Area

The ratio between the length and the breadth of a rectangular park is 3 : 2. If a man cycling along the boundary of the park at the speed of 12 km/hr completes one round in 8 minutes, then the area of the park (in sq. m) is:

Question:
The ratio between the length and the breadth of a rectangular park is 3 : 2. If a man cycling along the boundary of the park at the speed of 12 km/hr completes one round in 8 minutes, then the area of the park (in sq. m) is:

[A].

15360
[B].
153600
[C].
30720
[D].
307200

Answer: Option B

Explanation:

Perimeter = Distance covered in 8 min. = 12000 x 8 m = 1600 m.

60

Let length = 3x metres and breadth = 2x metres.

Then, 2(3x + 2x) = 1600 or x = 160.

Length = 480 m and Breadth = 320 m.

Area = (480 x 320) m2 = 153600 m2.

Read More The ratio between the length and the breadth of a rectangular park is 3 : 2. If a man cycling along the boundary of the park at the speed of 12 km/hr completes one round in 8 minutes, then the area of the park (in sq. m) is:

(A + B + C)’s 1 day’s work =	1	;
	6

(A + B)’s 1 day’s work =	1	;
	8

(B + C)’s 1 day’s work =	1	.
	12

Then,	120	+	480	= 8	1	+	4	=	1	….(i)
	x		y		x		y		15

Similar Posts