Let H = distance Hiro walked
4H - 10 = distance Rajesh walked
H + 4H - 10 = 25
5H - 10 = 25
5H = 35
Hiro walked 7 km so Rajesh walked 4(7) - 10 = <<7*4-10=18>>18 km
Rajesh walked <<18=18>>18 kilometers.
#### 18