Question

solve question no 7,8,9

Answer 1

9) we know that area of sector formulae is x/360 × πr^2 so ....x means teta
teta = 90 ° here pie = 22/7
radius = 3.5 /2 = 1.75
so 90/360×22/7×1.75×1.75
1/4×22/7×3.0625
1/2 × 11/7 × 3.0625
then 2.4062 is the answer

Answer 2

☆Hello friend☆

$area = \pi {r}^{2}$
7) Radius= 98m/2 = 49 m
C=2× 22/7 × 49 m
= 14 m×22
= 308 m
Time will take to cover 14 m = 1 min
1 meter= 1/14 min
308 m= 1/14× 308
= 22 mins





8) Perimter of rectangle= 2( 18+15)cm
= 66 cm

Circumference= 2×22/7 × r
66 cm×7/44= r
21/2 = r, radius= 21/2 cm

Area of circle= 22/7 × 21/2 cm× 21/2 cm
= 11 ×3 cm×21/2 cm
=346.5 cm^2



9a. Area of circle = 22/7 ×3.5 m×3.5 m
= 22× 0.5m×3.5 m
= 11 m × 3.5
= 38.5 m^2

As shaded region is 1 /4 th so it will be:-
38.5/4= 9.625 m^2

b. Area of circle = 22/7 × 7m × 7m
= 22 ×1 m× 7m
= 154 m^2

As its half shaded= 154 m^2/2= 77 m^2

Hope it helps

☺☺☺