The surface area of a cuboid is 1372 cm2. If its dimensions (l:b:h) are in the ratio 4 : 2 : 1, then its length(in cm) is:
28 cm
Surface Area = 1372 cm2 (Given)
Let length, breadth and height be l, b and h respectively
⇒2(l×b+b×h+l×h)=1372
Since, it is given that
l:b:h = 4:2:1
Let l=4k, b=2k and h=k
∴2(4k×2k+2k×k+4k×k)=1372
28k2=1372
k2=49⇒k=7
∴l=4k=4×7=28 cm