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सी.आई.एस.सी.ई.आईसीएसई ICSE Class 8

The Height of a Rectangular Solid is 5 Times Its Width and Its Length is 8 Times Its Height. If the Volume of the Wall is 102.4 Cm3, Find Its Length. - Mathematics

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प्रश्न

The height of a rectangular solid is 5 times its width and its length is 8 times its height. If the volume of the wall is 102.4 cm3, find its length.

योग
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उत्तर

Height of rectangular solid = 5 × width
and length = 8 × height = 8 × 5 × width = 40 × width
Volume = 102.4 cm3
Let width = w
Then height = 40w
and height = 5w

`therefore "w" xx 40"w" xx 5"w" = 102.4`

`"w"^3 = 102.4/(40 xx 5) = 0.512`

= `(0.8)^3`

∴ w = 0.8

∴ Length = 40w = `40 xx 0.8`

= 32 cm

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अध्याय 21: Surface Area, Volume and Capacity - Exercise 21 (C) [पृष्ठ २४१]

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सेलिना Concise Mathematics [English] Class 8 ICSE
अध्याय 21 Surface Area, Volume and Capacity
Exercise 21 (C) | Q 6 | पृष्ठ २४१

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