Higher June 2017 Paper 1 Q3
3. The scale drawing below shows a lake.
There are two small islands in the lake at A and B.
The lifeguard station is marked at C.
Swimming is only allowed in the area of the lake that is,
- nearer to A than it is to B and
- less than 60 metres from C.
Using a ruler and a pair of compasses, show accurately on the diagram the area where swimming is allowed.
Shade the area where swimming is allowed.
Use the scale 1 cm represents 10 m. [4]
On screen this diagram may not be shown at actual size. To measure it, use the question paper (PDF) printed at 100%.
| Scheme | Marks | Comments |
|---|---|---|
| Arc (of circle) centre C radius 6 cm \(\pm\) 2mm | B1 | |
| Correct perpendicular bisector construction with appropriate arcs | B2 | Tolerance \(\pm\) 2mm and \(\pm\) 2\(^\circ\) Award B1 for appropriate arcs and no line or line outside of tolerance ie no arcs no marks |
| Correct area shaded or indicated | B1 | FT provided a closed region bounded by an attempt at a perpendicular bisector, with or without arcs, and the arc of a circle centre C |
| (4) |