Date | May 2017 | Marks available | 5 | Reference code | 17M.2.SL.TZ2.S_9 |
Level | Standard Level | Paper | Paper 2 | Time zone | Time zone 2 |
Command term | Find | Question number | S_9 | Adapted from | N/A |
Question
A ship is sailing north from a point A towards point D. Point C is 175 km north of A. Point D is 60 km north of C. There is an island at E. The bearing of E from A is 055°. The bearing of E from C is 134°. This is shown in the following diagram.
When the ship reaches D, it changes direction and travels directly to the island at 50 km per hour. At the same time as the ship changes direction, a boat starts travelling to the island from a point B. This point B lies on (AC), between A and C, and is the closest point to the island. The ship and the boat arrive at the island at the same time. Find the speed of the boat.
Markscheme
valid approach for locating B (M1)
egBE is perpendicular to ship’s path, angle
correct working for BE (A1)
eg
valid approach for expressing time (M1)
eg
correct working equating time (A1)
eg
27.2694
27.3 (km per hour) A1 N3
[5 marks]