Question

the length and breadth of a rectangle are 5.7+_0.1
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Answer 1

Here your answer

Here, l=(5.7±0.1)cm,b=(3.4±0.2)cm

Area, A = l×b=5.7×3.4=19.38cm2=19.0cm2 (rounding off to two significant figures)

∴A△A=±(l△l+b△b)

∴A△A=±(l△l+b△b)= ±(5.70.1+3.40.2)=±(5.7×3.40.34+1.14)=±19.381.48

⇒△A=±19.381.48×A=±19.381.48×19.38=±1.48

⇒△A=±19.381.48×A=±19.381.48×19.38=±1.48△A=±1.5 (rounding off to two significant figures);

⇒△A=±19.381.48×A=±19.381.48×19.38=±1.48△A=±1.5 (rounding off to two significant figures);Area = (19.0±1.5)cm