Question

The surface area of a cuboid is 1372sq.cm if its dimension in the ratio 4:2:1,then its length is

Answer 1

1372 is the TSA of cuboid
and the given ratio is.
4x+2x+1x=1327
7x=1327
x=1327/7
x=189.57 l .. ans

Answer 2

Answer:

TSA = 1372 cm^2

ratio = 4:2:1

So ,

l = 4x

b = 2x

h = 1x

TSA = 2(lb+bh+hl)

1372=2( (4x)(2x) + (2x)(1x) + (1x)(4x) )

1372 = 2 × 14x^2

1372 = 28x^2

1372÷28 = x^2

49 = x^2

√49 = x

7 = x

SO ,

l = 4 × 7

l = 28 cm