Question

1. If a/b is a rational number in its lowest
form. What is the condition on 'b' so that the decimal
representation of a/b is terminating.​

Answer 1

Given:

Length of cuboid = 15 cm

Breadth of cuboid = 5 cm

Height of cuboid = 2 m = 2 × 100 = 200 cm

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To find:

Volume of cuboid?

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Solution:

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$\setlength{\unitlength}{0.75cm}\begin{picture}(12,4)\linethickness{0.3mm}\put(6,6){\line(1,0){5}}\put(6,9){\line(1,0){5}}\put(11,9){\line(0,-1){3}}\put(6,6){\line(0,1){3}}\put(4,7.3){\line(1,0){5}}\put(4,10.3){\line(1,0){5}}\put(9,10.3){\line(0,-1){3}}\put(4,7.3){\line(0,1){3}}\qbezier(6,6)(4,7.3)(4,7.3)\qbezier(6,9)(4,10.2)(4,10.3)\qbezier(11,9)(9.5,10)(9,10.3)\qbezier(11,6)(10,6.6)(9,7.3)\put(8,5.5){\sf{15 cm}}\put(4,6.3){\sf{5 cm}}\put(11.4,7.5){\sf{200 cm}}\end{picture}$

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We know that,

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$\star\;{\boxed{\sf{\purple{Volume_{\;(cuboid)} = l \times b \times h}}}}$

$:\implies\sf 15 \times 5 \times 200$

$:\implies{\boxed{\sf{\pink{15000\;cm^3}}}}\;\bigstar$

$\therefore\;{\underline{\sf{Hence,\;Volume\;of\;cuboid\;is\; \bf{15000\;cm^3}.}}}$

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

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

Curved surface area of cuboid = 2(l + b)h

Total surface area of cube = 6a²

Cuved surface area of cube = 4a²

Volume of cube = a³