Question

Find the correFind the correct relation between number of painters and length of the wall ct relation between number of painters and length of the wall

Answer 1

Answer:

Here number of painters are in direct proportion to length the wall and inversely proportional to number of days.

No. of painterLength of wall (m)No. of days121803x200512:x180:200=9:103:5Number of painters α length of the wall

12:x=9:10......... (1) and 

Number of painters αnumberofdays1

12:x= inverse ratio of 3:5

12:x=5:3........(2)

from (1) and (2)

12:x= compound ratio of 9:10 and 5:3

12:x=(9:10)×(5:3)

12:x=9×5:10×3

12:x=45:30=3:2

3×x=12×2

x=324=8

Number of painter required =8

Answer 2

Question :

Find the correct relation between number of painters and length of the wall.

Answer :

The painter’s fee is given by nKAh where n is the number of walls, K is a constant with units of dollars per square foot, A is the length of each wall in feet, and h is the height of each wall in feet.

Examining this equation shows that A and h will be used to determine the area of each wall. The variable n is the number of walls, so n times the area of the walls will give the amount of area that will need to be painted.

The only remaining variable is K, which represents the cost per square foot and is determined by the painter’s time and the price of paint.

Therefore, K is the only factor that will change if the customer asks for a more expensive brand of paint.