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14  (a)  (i)  Cross-section area                         = 331.765 + 932.803
                                  1            360                         = 1264.6 cm 2                     [4]
                             = 5 ×    × 5 × 5 × sin
                                  2             5                      (d)  Bearing of S from P = 90°+ ∠SPQ
                             = 59.441 cm 2                  [3]            = 90° + 112.558°
                         (ii)  Volume = 59.441 × 20                        = 202.6°                          [1]
                                    = 1188.82 cm 3          [1]    2   (a)   sin ∠QRP  =  sin ∠QPR
                      (b)  Mass =1188.82 × 13.5 g                             QP        QR
                              = 16049.07 g                                 sin ∠QRP =  100 sin 55
                              = 16.05 kg                    [2]                         110
                      (c)  1 m  × 0.9 = 0.9 m                              ∠QRP = 48.132°
                             3
                                        3
                                  = 900000 cm 3                            ∠PQR = 180° – 55° – 48.132°
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                          Number of prisms                                      = 76.868°                    [4]
                            900000                                     (b)  (i)  Bearing of R from Q
                          =
                            1188.82                                           = 180° – (360° – 345°)
                          = 757.05                                            = 165°                         [1]
                          ∼  757 prisms                     [3]           (ii)  Bearing of Q from P
                  15  Volume of the box                                       = 180° – (360° – 165° – 76.868°)
                        = (1.4 cm × 2 × 4) × (1.4 cm × 2 × 4) × (1.4 cm × 2)           = 61.9°               [2]
                      = 351.232 cm 3                                   (c)    PR   =   QR
                      Volume of 16 balls                                   sin PQR   sin QPR
                            4                                                        110 sin 76.868
                      = 16 ×    × π × 1.4 3                                     PR =
                            3                                                           sin 55
                         21952                                                     = 130.77 m
                      =        π cm 3
                          375                                              Distance
                      Percentage of the balls that occupied the box        = 130.77 × cos (345° – 270° – 48.132°)
                        21952                                              = 116.65 m                        [5]
                      =      π ÷351.232
                         375                                           (d)  Area =   1  (PQ)(QR) sin ∠PQR
                        1                                                        2
                      =   π%                                [6]
                        6                                                      =  1  (100)(110) sin 76.868
                                                                                 2
                     6 6  Trigonometry                                         = 5356.17 m 2                 [2]
                                                                   3   (a)  ∠PQR = 360° – 90° – 240°
                       Trigonometry                                             = 30° (shown)                [1]
                                                                       (b)  (i)  PR  = PQ  + QR  – 2(PQ)(QR) cos ∠PQR
                                                                                2
                                                                                           2
                                                                                     2
                                                                                           2
                                                                                2
                                                                                      2
                  1   (a)  SR  = SQ  + QR  – 2(SQ)(QR) cos ∠SQR               PR  = 11.5  + 20  – 2(11.5)(20) cos 30°
                            2
                                 2
                                      2
                          75  = 45  + 45  – 2(45)(45) cos ∠SQR                PR = 11.57 km                  [4]
                                     2
                                2
                            2
                          ∠SQR = 112.885°                   [4]           (ii)  sin ∠PRQ   =   sin 30°
                           sin ∠SPQ   sin ∠PQS                                   11.5     11.57
                      (b)            =
                              SQ         PS                                   ∠PRQ = 29.8°
                            sin ∠SPQ =  (  45 sin 38° )                           Bearing of P from R
                                                                              = 180° – 90° – 30° – 29.8°
                                          30
                               ∠SPQ = 180° – 67.442°                          = 30.2°                        [5]
                                     = 112.558°                        (c)  Total time used
                             PQ         PS                                 = 5.5 h – 20 min – 20 min
                                    =                                        29
                          sin ∠PSQ   sin ∠PQS                              =    h
                                     30 sin 29.442                            6
                                PQ =                                       Total distance travelled
                                        sin 38°
                                    = 23.95 cm              [7]              = 11.5 km + 20 km + 11.57 km
                                                                           = 43.07 km
                      (c)  Area of PQRS                                    Speed of running
                          = Area of ΔPQS + Area of ΔSQR
                            1                   1                          =  43.07 km
                          =   (PQ)(QS) sin ∠PQS +   (SQ)(QR)                   29
                            2                   2                                 h
                            sin ∠SQR                                            6
                            1                  1                           = 8.91 km/h                       [3]
                          =   (23.95)(45) sin 38° +   (45)(45)     4   TS  = TR  + RS 2
                                                                              2
                                                                         2
                            2                  2                              2   2
                            sin 112.885°                                  = 15  + 20
                                                                       TS = 25 cm
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                                         TM
                  172     Ace Your Mathematics

         Answers.indd   172                                                                                      15/03/2022   11:08 AM
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