Question

find perimeter of arectangle whose length and breadth is8cm,70mm​

Answer 1

Perimeter of rectangle =2[l+b]units

l=8cm,b=70mm

1cm=10mm

70mm=7cm

Perimeter of rectangle

=2[8+7]

=2[15]

=30cm

Answer 2

$\sf Given \begin{cases} & \sf{Length\;of\;rectangle = \bf{8\;cm}} \\ & \sf{Breadth\;of\;rectangle = \bf{70\;mm\;=\;7\;cm}} \\ \end{cases}$

Need to find: perimeter of rectangle?

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$\dag\;{\underline{\frak{We\;know\;that,}}}$

$\star\;{\boxed{\sf{\purple{Perimeter_{\;(rectangle)} = 2(length + breadth)}}}}$

$:\implies\sf Perimeter_{\;(rectangle)} = 2(8 + 7)$

$:\implies\sf Perimeter_{\;(rectangle)} = 2 \times 15$

$:\implies{\boxed{\sf{\pink{Perimeter_{\;(rectangle)} = 30\;cm}}}}\;\bigstar$

$\therefore\;{\underline{\sf{Thus,\; Perimeter\;of\;rectangle\;is\; \bf{30\;cm}.}}}$

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$\qquad\qquad\boxed{\underline{\underline{\purple{\bigstar \: \bf\:More\:to\:know\:\bigstar}}}}$

• Area of Rectangle = Length × Breadth

• Diagonal of Rectangle = √(l² + b²)

• Perimeter of square = 4 × side

• Area of square = side × side

• Diagonal of square = a√2