Very simple first equation application problem, first give 20, write good add 100 ah! A car drove from a to B at the speed of 60 km / h. After 4.5 hours of driving, the average driving speed was reduced by 20 km / h due to rain. As a result, it arrived at B 45 minutes later than expected Method 1: set the scheduled time as X Method 2: set the driving distance after rain as X km Method 3: set the distance between a and B as X kilometers PS: all three should be written. Well written, give 100!

Very simple first equation application problem, first give 20, write good add 100 ah! A car drove from a to B at the speed of 60 km / h. After 4.5 hours of driving, the average driving speed was reduced by 20 km / h due to rain. As a result, it arrived at B 45 minutes later than expected Method 1: set the scheduled time as X Method 2: set the driving distance after rain as X km Method 3: set the distance between a and B as X kilometers PS: all three should be written. Well written, give 100!

Method 1: set the scheduled time as X (distance as equivalent relationship) 60x = 60 * 4.5 + (60-20) * 45 / 60 method 2: set the driving distance after rain as XKM (time as equivalent relationship) (60 + x) / 60 = [4.5 + X / (60-20)] - 45 / 60 method 3: set the distance between a and B as XKM (time as equivalent relationship)