Question

conte
4. A pen stand made of wood is in the shape of a
Fig. 13.15
cuboid with four conical depressions to hold pens.
The dimensions of the cuboid are 15 cm by 10 cm by
3.5 cm. The radius of each of the depressions is 0.5
cm and the depth is 1.4 cm. Find the volume of
wood in the entire stand (see Fig. 13.16).
​

Answer 1

Answer:

523.53 cm^3

Step-by-step explanation:

height of depression (h) = 1.4cm

radius of depression (r) =  0.5 cm

volume of wood in entire stand = volume of cuboid - (4 * volume of depression)

• lbh - 4×1/3 πr^2h
• 15 ×10×3.5 - 4×1/3×22/7×1/2×1/2×1.4=
• 525 - 1.47 =
• 523.53cm^3

hope this help you

Answer 2

Step-by-step explanation:

l=15cm

b=10cm

h=3.5cm

vol.of cuboidal stand=lbh

=15*10*3.5

=525 cm3.

r=0.5cm

h=1.4cm

vol.of conical depression =1/3πr*r*h

=1/3*22/7*1/2*1/2*1/4

=0.367cm3

Now,

vol. of entire wood= vol.of cuboidal stand - vol.of 4conical depression

=525 - 4*0.367

=523.532cm3