In a paint factory, an old conveyer line has filled 10 barrels of paint, and is filling more at a rate of 3 barrels per minute. A worker just switched on a newer line that can fill 4 barrels per minute. In a little while, the two lines will have filled an equal number of barrels. How many barrels will each line have filled?

40 barrels

Step-by-step explanation:

Given that:

Let x = number of minutes

Old conveyor line :

Filling rate = 3 barrels per minute

Already filled = 10 barrels

Equation :

10 + 3x - - - (1)

NEW conveyor line:

Filling rate = 4 barrels per minute

Equation :

4x - - - (2)

Equate equation (1) and (2)

10 + 3x = 4x

10 = 4x - 3x

10 = x

Hence, in 10 minutes, each line will have filmed same number of barrels which is

4x = 4*10 = 40 barrels

10 + 3x = 10 + 3(10) = 40 barrels