Question

If the length, breadth and height of a cube are decreased, decreased and increased by 5%, 5% and 20% respectively, then what will be the impact on the surface area of the cube (in percentage terms)?

Answer 1

let the
length be x
breadth be y
height be z
then
surface area
2(xy+xz+yz)
after changing
length =x-5x/100=95x/100
breadth=y-5y/100=95y/100
height=120z/100=12z/10
by putting the value
2(95x/100×95y/100+95x/100×12z/10+

Answer 2

Thank you for asking this question. Here is your answer:

Surface =6x^2=2(lb+bh+lh)

=2(0.95x*0.95x+0.95x*1.2x+0.95x*1.2x)

=1.9(0.95x^2+1.2x^2+1.2x^2)

= 1.9(3.35x^2)

=6.365x^2

the percentage increase would be 6.365/6*100–100

6.1% is the increase in surface area

If there is any confusion please leave a comment below.