In the past, there was a street lamp every 25 meters on one side of an expressway, and there were 9 1 street lamp at both ends. Now all of them are replaced by new energy-saving lamps, and only 46 lamps are installed at both ends. How many meters is there between two adjacent lamps?

25×(9 1- 1)÷(46- 1)

=25×90÷45

=2250÷45

=50 meters