Higher November 2020 Paper 2R Q7
7 Markus makes a steel framework.
The framework is in the shape of the right-angled triangle \(ABC\) shown in the diagram.
Diagram NOT accurately drawn
The steel that Markus uses costs $22 per metre.
The steel can only be bought in a length that is a whole number of metres.
Work out the total cost of the steel that Markus buys in order to make the framework.
(4)
| Scheme | Marks |
|---|---|
| \(4.3^2 + 6.4^2\) or 59.45 | M1 |
\(\sqrt{4.3^2 + 6.4^2}\) or \(\sqrt{59.45}\) or 7.71(038…) or 7.7 | M1 |
| e.g (‘7.71’ + 4.3 + 6.4) × 22 or ’18.4’ × 22 (=404.8) or (‘8’ + 4.3 + 6.4) × 22 or ’18.7’ × 22 or ‘19’ × 22 or ‘20’ × 22 | M1 |
| $418 | A1 |
| (4) | |
| (4 marks) |
Notes
M1: for squaring and adding
M1: dep 1st M1 for square rooting
M1: dep M2 for a non-rounded perimeter × 22
or 19 × 22
accept 20 × 22 oe
A1: cao