Question
A boat's speed in still water is 200% greater than the
speed of the stream. The boat takes 13 hours to travel 180 km downstream and 66 km upstream. How much time will it take for the boat to cover a distance of 120 km downstream?Solution
Let the speed of stream be x km/h
So, the speed of the boat in still water = x + 2x = 3x km/h
So, downstream speed = 3x + x = 4x km/h
So, upstream speed = 3x – x = 2x km/h
According to question:
180/4x + 66/2x = 13
45/x + 33/x = 13
78/x = 13
x = 78/13, x = 6
So, downstream speed = 4 × 6 = 24 km/h
So, time taken to cover 120 km downstream = 120/24 = 5 hours
Statement : Some letters are alphabets.
All alphabets are words.
Some letters are consonants.
Conclusion : I. All letters being...
In each of the questions below are given three statements followed by two conclusions numbered I and II. You have to take the given statements to be ...
Statement:Â
All beds are cupboards.
Some beds are tables.
Some tables are pillows.
Conclusion:
I. Some cupboards are...
In the question below there are two conclusions followed by three statements in the options. You have to take the three given statements to be true ev...
Statements:
No Summer is Winter.
Only a few Winter is Autumn
Some Summer are Spring.
Conclusions:
I. All W...
Statements:Â
Only a few Twitter are Meta.
Some Meta are Tiktok.
No Tiktok is Instagram.
Conclusions:
I. Some Twi...
Direction: In the given question a statement is followed by two conclusions numbered I and II. You have to assume everything in the statement to be tru...
Statements:
Some schools are hospitals
Mostly hospitals are courts
Some courts are parlours
Conclusions:
I...
In the question below there are three statements followed by three conclusions I, II and III. You have to take the four given statements to be true eve...
, In the question below some statements are given followed by two conclusions I and II. You have to take the given statements to be true even if they s...
