Find the radius of the circle.

This circle is the base of a solid cylinder of height 25 cm.

Write down the volume of the solid cylinder.

This circle is the base of a solid cylinder of height 25 cm.

Find the total surface area of the solid cylinder.

πr² = 8     (M1)

Note: Award (M1) for correct area formula.

r = 1.60 (cm)     (1.59576...)     (A1)     (C2)

[2 marks]

200 cm³     (A1)(ft)     (C1)

Notes: Units are required. Follow through from their part (a). Accept 201 cm³ (201.061…) for use of r = 1.60 .

[1 mark]

Surface area = 16 + 2π(1.59576...)25     (M1)(M1)

Note: Award (M1) for correct substitution of their r into curved surface area formula, (M1) for adding 16 or 2 × π × (their answer to part (a))²

267 cm²     (266.662...cm²)     (A1)(ft)     (C3)

Note: Follow through from their part (a).

[3 marks]

There were two common errors identified on a number of scripts in this question. In part (a), the majority of candidates correctly wrote down πr² = 8 for method but a significant number of candidates then went on to write down r = 2.55 (forgetting to square root). Such candidates were able to recover in subsequent parts of the question with the allowable follow through marks, but a method mark and final accuracy mark was lost on many scripts in part (c) with incomplete methods shown for the total surface area of the cylinder. Leaving off the addition of either one or both end surfaces of the cylinder resulted in the final two marks being lost.

There were two common errors identified on a number of scripts in this question. In part (a), the majority of candidates correctly wrote down πr² = 8 for method but a significant number of candidates then went on to write down r = 2.55 (forgetting to square root). Such candidates were able to recover in subsequent parts of the question with the allowable follow through marks, but a method mark and final accuracy mark was lost on many scripts in part (c) with incomplete methods shown for the total surface area of the cylinder. Leaving off the addition of either one or both end surfaces of the cylinder resulted in the final two marks being lost.

There were two common errors identified on a number of scripts in this question. In part (a), the majority of candidates correctly wrote down πr² = 8 for method but a significant number of candidates then went on to write down r = 2.55 (forgetting to square root). Such candidates were able to recover in subsequent parts of the question with the allowable follow through marks, but a method mark and final accuracy mark was lost on many scripts in part (c) with incomplete methods shown for the total surface area of the cylinder. Leaving off the addition of either one or both end surfaces of the cylinder resulted in the final two marks being lost.