SSC (English Medium) Class 8Maharashtra State Board
Share
Notifications

View all notifications

If 15 Workers Can Build a Wall in 48 Hours, How Many Workers Will Be Required to Do the Same Work in 30 Hours ? - SSC (English Medium) Class 8 - Mathematics

Login
Create free account


      Forgot password?

Question

If 15 workers can build a wall in 48 hours, how many workers will be required to do the same work in 30 hours ? 

Solution

The number of hours required to build a wall is inversely proportional to the number of workers employed.

Let the number of hours be h and the number of workers be w.

Here, h varies inversely as w i.e. \[h \propto \frac{1}{w}\].

∴ \[h = \frac{k}{w}\] , where is k is constant of variation

⇒ h × w = k

When h = 48, w = 15.

∴ k = 48 × 15 = 720

So, the equation of variation is hw = 720.

When h = 30,

30w = 720

⇒ w = \[\frac{720}{30}\] = 24

Thus, the number of workers required to do the same work in 30 hours is 24.

  Is there an error in this question or solution?

APPEARS IN

 Balbharati Solution for Balbharati Class 8 Mathematics (2019 to Current)
Chapter 7: Variation
Practice Set 7.3 | Q: 2 | Page no. 40
Solution If 15 Workers Can Build a Wall in 48 Hours, How Many Workers Will Be Required to Do the Same Work in 30 Hours ? Concept: Time, Work, Speed.
S
View in app×