X new energy-saving lamps can be installed and need to be replaced. According to the equivalence relation: the total length of the road in the two street lamp installation methods is the same, just list the equation and solve it.

explain

Solution:

X new energy-saving lamps need to be replaced.

There is an equation according to the meaning of the question:

54(x- 1)= 36( 106- 1)

54x=3834

x=7 1

There are 7 1 new energy-saving lamps to be replaced.