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प्रश्न
The volume of a wall, 5 times as high as it is broad and 8 times as long as it is high, is 128 m3. The breadth of the wall is
पर्याय
30 cm
40 cm
22.5 cm
25 cm
उत्तर
40 cm
Let the breadth of the wall be x cm.
Then, its height = 5x cm
and its length = (8 × 5x)
= 40 × cm
Hence, the volume of the wall = (40x × x × 5x) cm3
It is given that the volume of the wall = 128 m3.
Therefore,
⇒ 40x × x × 5x = 128 × 100 × 100 × 100
⇒ 200x3 = 128000000
⇒ x3 = 640000
⇒ x3 = (40 × 40 × 40)
⇒ x = 40 cm
Notes
Note : It should be 128 m3 instead of 12.8 m3
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