Question

The sides of a rectangular are (10.5 ± 0.2) cm and (5.2 ± 0.1) cm. Calculate its

perimeter with error limits.

Answer 1

Length = (10.5+/- 0.2)
Breadth =(5.2+/-0.1)
l=10.5
delta l=0.2
b=5.2
delta b= 0.1
perimeter P= 2(l+b)
=2(10.5+5.2)
=2(15.7)
=31.4cm
Absolute error in perimeter = delta P= +/- 2(delta l + delta b)
= +/- 2(0.2+0.1)
=+/- 2(0.3)
= +/- 0.6cm
Perimeter with error limits
(P+/- delta P) = (31.4+/- 0.6)cm
I put +/- means plus or minus, in my keyboard plus or minus symbol doesn't have that's why ok.
Hope you got it.

Answer 2

Answer:

The Perimeter of the rectangle with error limits :

$P$ ± Δ$P$ = $(31.4$ ± $0.6 cm)$

Explanation:

It is given that the length $= (10.5$ ± $0.2)$

Breadth $=(5.2$ ± $0.1)$

$l=10.5$

Δ $l=0.2$

$b=5.2$

Δ $b= 0.1$

Perimeter of a rectangle $P= 2(l+b)$

$=2(10.5+5.2)$

$=2(15.7)$

$=31.4cm$

Absolute error in perimeter Δ$P=$ ± $2($ Δ$l+$ Δ$b)$

$=$ ± $2(0.2+0.1)$

$=$± $2(0.3)$

$=$ ± $0.6cm$

Therefore, perimeter with error limits :

$P$± Δ$P =$ $(31.4$ ± $0.6cm)$