Mathematics · May / June 2021 · Paper 41 · Question 3

2.64 or 2.638… [4]

π × 2.4 2 + π × 2.4 × 6.3 2 = oe

M3 for [ R ] π + 2 π

or M2 for 1 π × 2.4 2 + π × 2.4 6.3 × = π R 2 + × 4 π R 2 2

or M1 for [ π × 2.4 ] 2 + π × 2.4 × 6.3 oe 1 or [ π R 2 ] + × 4 π R 2 oe 2

953 or 952.6 to 952.8 [7]

4 3 1 16 − 12 × π × 2 × × −

M3 for 7.6 16 1 3 16 1 1 or × π × 7.6 2 × 16 − × π × 1.9 2 × ( 16 12 − ) 3 3 OR 3 16 − 12

B1 for top radius = 1.9 or oe 16

M2 for 1 1 2 2 × π × 7.6 × 16 − × π × ( their 1.9) × ( 16 12 − ) 3 3 3 1 16 − 12 2 or × π × 7.6 × 16 × 1 − their 3 16 1 2

or M1 for 3 π × × 7.6 × 16 1 or for × π × ( their 1.9) 2 × ( 16 12 − ) 3