Question

18. A geometrical shape lig I consisting of three semictroles PSR, RTQ and PAQ of diameters 21 cm, 14
cm and 7 cm respectively had drawn on ſoor. Amit and Amar takes turn in running in a closed loop that
is to end where each one starts. The fastest to complete the loop wins the game. Amit gets turn and
follow path. Amit's path in shown in Fig. II with speed 1. 5 m/sec Amar's path (RSPOTR) is shown in
fig III with speed 1.4m/sec.
(RSDAQTR)
Answer the following questions:
Which of the following is true?
F(A) Amit e path is longer than Amar's path
(B) Amar's path is longer than Amit's path
© Amit's path and Amar's path are equal in length
(D)None of these
Distance covered by Amar is:
(A) 58 m
(B) 66 m
(C) 88 m
CIH Area swept by closed loop of Amit's journey is
(A) 125 m
(B) |12,5 m
(C) 1155 m
(D) 44 m
(D) 125.5 m?
Time taken by Amit to cover the journey is:
(A) 66 sec.
(B) 44 seo.
(C) 55 sec.
(D) 40 sec
Game is won by:
(A) Amit
winner,
(B) Amur
(D) game is tied
(D) both are joint​

Answer 1

Answer:

Answer

Correct option is

A

31.4

Radius of semicircle PSR=

2

1

×10=5cm

Radius of semicircle RTQ=

2

1

×3cm=1.5cm

Radius of semicircle PAQ=

2

1

×7=3.5cm

Perimeter of shaded region = Circumference of semicircle PSR+ Circumference of semicircle RTQ+ Circumference of semicircle PAQ

Threfore,

Perimeter of shaded region =π×5+π×1.5+π×3.5=10π=31.4