Question

A toy is in the form of cylinder with hemispherical ends. if the whole length of the toy is 90 cm and its diameter is 42 cm find the cost of painting the toy @ 70 Paisa per square centimetre

Answer 1

Answer:

Step-by-step explanation:

Total height of toy = 90cm.

Height of cylinder = 90-(2X21)

= 48cm

Area of cylinder =2pi rh

= 2 pi 21 X 48

= 2016 pi

Area of hemisphere =4 pi r^2

=pi X 21 X 21

 = 1764 pi

Total area = 1764 pi + 2016 pi

= pi (1764+2016)

= pi (3780) cm sq.

Cost =3780 X pi X 70

= 8316 rupees.

Answer 2

Hey mate...

Here is your answer

Details of the cylinder :
Diameter =42
Radius =42/2=21cm
Height =90-(21+21)
=48cm

Details of the hemisphere :
Radius =21cm

Surface area of the toy =CSA of cylinder + CSA
Of hemisphere.

=
$2\pi \: rh + 2 \times 2\pi \: r {}^{2}$
$2\pi \: r(h + 2r)$
$2 \times 22 \div 7 \times 21(48 + 42)$
$132 \times (48 + 42)$
$132 \times 90$

$= 1188cm {}^{2}$
Cost of painting the toy =70 paise / cm^2

Cost of painting 1188 cm^2= 1188 × 70
=8316 paise
=83.16 Rs

Hope my answer will help you...