4400 Higher November 2009 Paper 3 Q10

EdexcelHigherOld spec3 marksPrisms

10 The diagram shows a prism.
The cross section of the prism is a right-angled triangle.
The lengths of the sides of the triangle are 8 cm, 15 cm and 17 cm.
The length of the prism is 20 cm.

Work out the total surface area of the prism.

Triangular prism with right-angled triangle cross-section of sides 8 cm, 15 cm and 17 cm, and length 20 cm

Diagram NOT accurately drawn

(3)

Mark scheme

Scheme	Marks
2 × (0.5 × 8 × 15) + (17 × 20) + (15 × 20) + (8 × 20)	M1
2 × 60 + 340 + 300 + 160	M1
920	A1
	(3)
	(3 marks)

Notes

M1: 1 correct face 60, 340, 300 or 160

M1: All correct faces added 120 ≡ 2 × 60