Question

the volume of cubiod is 3600 cubic metre. and it's height is 12cm the cross section is a rectangle whose length and breadth are i ratio 4:3 .find the perimeters ofthe cross section ​

Answer 1

Let l =4x

   B=3x 

  h =12cm

 V = L×B×H=3600

  or 4x ×3x ×12 =3600

    12x²×12 =3600

  x² = 3600 \12×12

  or  x² =300\12

 or    x² =100\4 =25

or x = 5

then L =4×5=20 and B=3×5=15

L=20  B =15 ans.