Question

A cuboid is 3 cm by 4 cm by 7 cm.Explain whether doubling all dimensions would double the surface area.

Answer 1

Answer:

$\large\red{NO}$

Step-by-step explanation:

It is given a cuboid having dimension,

length, l = 7 cm

breadth, b = 4 cm

height, h = 3 cm

Now, We know that,

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

So, the surface area ,

S1 = 2( 7×4 + 4×3 + 3×7 )

=> S1 = 2( 28 + 12 + 21)

=> S1 = 2 × 51

$\bold{=> S1 = 102{cm}^{2}}$

Now, after doubling the dimension,

we have , new dimensions,

l' = 7×2 = 14 cm

b' = 4×2 = 8 cm

h' = 3×2 = 6 cm

So,the new surface area,

S2 = 2(14×8 + 8×6 + 14×6 )

=> S2 = 2 × 244

$\bold{=> S2 = 488{cm}^{2}}$

Clearly, we can see that

2S1 ≠ S2

Hence, it is wrong assumption.

Answer 2

Step-by-step explanation:

hence proved make it as brainliest answer