Question

the length, breadth and thickness of a rectangular sheet of metal are 4•234 m ,1•005 m, and 2•01 cm respectively give the area and volume of the sheet to correct significant figures


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Answer 1

Explanation:

area of the top one =4.234×1.005

=4.25517

=4.255 (significant upto 4 digits)

volume =4.255×2.01

=8.55255

=8.55 (sign up to 3 dig)

Answer 2

Explanation:

Given:-

Length = 4.234 m

Breadth = 1.005 m

Height (thickness of sheet) = 2.01 cm = 0.0201 m

Solution:-

$Area \: = \: 2(lb \: + \: bh \: + hl) \\ = 2(4.234 \: \times1.005 \: + 1.005 \: \times 0.201 \: + \: 0.201\: \times \: 4.234) \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = \: 2(4.25517 + 0.0202005 + 0.08551034) \\ = (8.7209478) \\= 8.72 \: {m}^{2}$

Now,

$Volume \: = \: l \: \times \: b \: \times \: h \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 4.234 \: \times 1.005 \: \times \: 0.0201 \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: = 0.0855 \: m ^{3}$

$Hence \: The \: area \: is \: 8.72 \: m ^{2} \: \: and \: \\ Volume \: is \: 0.0855 {m}^{3}$