### 1. Speed of a speed-boat when moving in the direction perpendicular to the direction of the current is 25 km/h, speed of the current is 5 km/h. So, the speed of the boat against the current will be:

Answer: 15 km/hSol. Speed of boat = 25 – 5 = 20 km/h ∴ Speed of boat against the current = 20 – 5 = 15 km/h