Mathmetics
ISBT Mathmetics for all banking PO,Clerk,IBPS PO,Railway,SSC,IAS,OAS Exams
Q1. |
|
1) | 2 | 2) | 4 |
3) | 6 | 4) | 8 |
5) | None of these |
Answer : 6
Explanation :
Explanation :
Let,speed of boat man be x kmph.
So, speed in down stream =(x+2) kmph. and speed in up-stream = (x-2) kmph.
Since, distance is constant for both case ,
the equation = 2(x-2) = (x+2)
or 2x-4 = x+2
or x= 6 kmph

Q2. |
|
1) | 1 km/hr. | 2) | 1.5 km/hr. |
3) | 2 km/hr. | 4) | 3 km/hr. |
5) | None of these |
Answer : 1.5 km/hr.
Explanation :
Explanation :
Let, the speed of the stream be x km/hr.
Then, upward speed =(5- x)km/hr.
downward speed = (5 + x) km/hr.
So, (15/5+x) + (9/5-x) = 5
or x = 2 km/hr

Q3. |
|
1) | 3 km/hr. | 2) | 4 km/hr. |
3) | 6 km/hr. | 4) | 8 km/hr |
5) | None of these |
Answer : 3 km/hr.
Explanation :
Explanation :
Let, the speed of the stream be x km/hr.
Then, (91/10-x) + (91/10+x) = 20
or x = 3 km./hr

Q4. |
|
1) | 4 km/hr | 2) | 6 km/hr |
3) | 8 km/hr | 4) | 12 km/hr. |
5) | None of these |
Answer : 8 km/hr
Explanation :
Explanation :
Let, the speed of the man in still water be x km/hr and speed of the stream be y km/hr, then
(30/x-y) + (44/x+y) = 10 ......... (i)
(40/x-y) + (55/x+y) = 13 ........ (ii)
Solving equation. (I) and (II), we get x = 8 km/hr y = 3 km/hr

Q5. | A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is: |
1) | 2:1 | 2) | 3:2 |
3) | 2:3 | 4) | 3:1 |
5) | None of these |
Answer : 3:1
Explanation :
Explanation :
Let man's rate upstream be x kmph.
Then, his rate downstream = 2x kmph.
(Speed in still water) : (Speed of stream) = (2x+2) /2 : (2x-x)/2
=3x/2: x/2 = 3 : 1.

Q6. | A boat covers a certain distance downstream in 1 hour, while it comes back in 1 |
1) | 10kmph | 2) | 12kmph |
3) | 15kmph | 4) | 18kmph |
5) | None of these |
Answer : 15kmph
Explanation :
Explanation :
Let the speed of the boat in still water
be x kmph. Then,
Speed downstream = (x + 3) kmph,
Speed upstream = (x - 3) kmph.
(x
+ 3) x 1 = (x - 3)/2 x3
Or 2x + 6 = 3x - 9
Or x = 15 kmph.

Q7. | A man can row at 5 kmph in still water. If the velocity of current is 1 kmph and it takes him 1 hour to row to a place and come back, how far is the place ? |
1) | 2.4 km | 2) | 2.5km |
3) | 3km | 4) | 3.6km |
Answer : 2.4 km
Explanation :
Explanation :
Speed downstream = (5 + 1) kmph = 6 kmph.
Speed upstream = (5 - 1) kmph = 4 kmph.
Let the required distance be x km.
Then,x/6 +x/4 = 1
Or
2x + 3x = 12
Or 5x = 12
Or x = 2.4 km.

Q8. |
|
1) | 4 | 2) | 5 |
3) | 6 | 4) | 10 |
5) | None of these |
Answer : 5
Explanation :
Explanation :

Q9. | A man's speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr. The man's speed against the current is: |
1) | 7.5 km/hr | 2) | 8.5 km/hr |
3) | 10 km/hr | 4) | 12.5 km/hr |
5) | None of these |
Answer : 10 km/hr

Q10. |
|
1) | 3 km/hr | 2) | 5 km/hr |
3) | 8 km/hr | 4) | 9 km/hr |
5) | None of these |
Answer : 8 km/hr
Explanation : Speed in still water = ½(11 + 5) kmph = 8 kmph.
Explanation : Speed in still water = ½(11 + 5) kmph = 8 kmph.
