Question

[A] There are two boxes of metal sheet. The length, width and height of

a cuboidal box is 30 cm, 25 cm and 20 cm respectively. A cubical

box has each edge 25 cm find out how many cm² metal sheet is

used more to make which box ?

[B] The curved surface area of a right circular cylinder of height 14 cm

is 88 cm². Find the diameter of the base of the cylinder​

Answer 1

Step-by-step explanation:

As we need to find total sheet needed,that means by finding total area of cubical and cuboid .

surface area of cuboid = 2(lb+bh+hl)

= 2(30*25+25*20+20*30)

= 2( 750+ 500+600)

=2*1850 = 3700 cm. sq.

s.a of cubical box =6*s*s

=6*25*25

= 3750 cm. sq

Therefore 50 cm sq. more sheet is required to make cubical box.

B. C.S.A=88 cm.sq

h=14 cm

diameter of base =?

C.S.A = 2πrh

apply and find r. Then solve