Ml aggarwal solutions
Our top 5% students will be awarded a special scholarship to Lido.

Problems on Simultaneous Linear Equations | Problems on Simultaneous Linear Equations Exercise 6

Question 39

A boat sails a distance of 44 km in 4 hours with the current. It takes 4 hours 48 minutes longer

to cover the same distance against the current. Find the speed of the boat in still water and the

speed of the current.

Looking to do well in your science exam ?  
Learn from an expert tutor. Book a free class!

Let’s assume the speed of the boat in still to be x km/hr

And the speed of the current = y km/hr

Speed of the boat in the direction of current = (x + y) km/hr

Speed of the boat against the current = (x - y) km/hr

We know, distance = speed x time

Then according to the given conditions in the problem, we have

44 = (x + y) x 4

x + y = 44/4

x + y = 11 … (i)

And,

x – y = 5 … (ii)

Now, adding equations (i) and (ii) we have

x + y = 11

x – y = 5


2x = 16

x = 16/2

x = 8

On substituting the value of x in (i), we get

8 + y = 11

y = 11 – 8

y = 3

Therefore, the speed of the boat in still water = 8 km/hr and speed of the current = 3 km/hr.

Set your child up for success with Lido, book a class today!

Our top 5% students will be awarded a special scholarship to Lido.

subject-cta

Question 39

A boat sails a distance of 44 km in 4 hours with the current. It takes 4 hours 48 minutes longer

to cover the same distance against the current. Find the speed of the boat in still water and the

speed of the current.

Looking to do well in your science exam ? Learn from an expert tutor. Book a free class!

Let’s assume the speed of the boat in still to be x km/hr

And the speed of the current = y km/hr

Speed of the boat in the direction of current = (x + y) km/hr

Speed of the boat against the current = (x - y) km/hr

We know, distance = speed x time

Then according to the given conditions in the problem, we have

44 = (x + y) x 4

x + y = 44/4

x + y = 11 … (i)

And,

x – y = 5 … (ii)

Now, adding equations (i) and (ii) we have

x + y = 11

x – y = 5


2x = 16

x = 16/2

x = 8

On substituting the value of x in (i), we get

8 + y = 11

y = 11 – 8

y = 3

Therefore, the speed of the boat in still water = 8 km/hr and speed of the current = 3 km/hr.

Our top 5% students will be awarded a special scholarship to Lido.

subject-cta
Connect with us on social media!
2021 © Quality Tutorials Pvt Ltd All rights reserved
`