& lt2> solution: suppose that tomatoes have x kilograms.

5 times = 50

X = 4/5 of 50.

X = 50× 5/4

X = 125 in half.

3 & lt 1 & gt； Solution: Assume that the distance between Party A and Party B is X kilometers.

2x = 180。

X = 180 ÷ 2/3

X = 180× 3/2

x=270

& lt2> solution: It takes x hours to set up the whole process.

180÷2x=270

90x=270

x=270÷90

x=3