A cylinder with base radius 8 cm and height 2cm is melted to for

Subject

Quantitative Aptitude

Class

SSCCGL Class 12

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 Multiple Choice QuestionsMultiple Choice Questions

61.

The average of five consecutive positive integers is n. If the next two integers are also included, the average of all these integers will

  • increase by 1.5

  • increase by 1

  • remain the same

  • remain the same

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62.

If a hemisphere is melted and four spheres of equal volume are made, the radius of each sphere will be equal to

  • 1 fourthth of the radius of the hemisphere
  • radius of the hemisphere

  • 1 half of the radius of the hemisphere
  • 1 half of the radius of the hemisphere
231 Views

63.

If a shopkeeper wants to give 20% discount on a toy, he has to sell it for Rs.300. If he sells it at Rs. 405, then his gain percent is

  • 5%

  • 4%

  • 8%

  • 8%

477 Views

64.

The average age of 30 students of a class is 14 years 4 months. After admission of 5 new students in the class the average becomes 13 years 9 months. The youngest one of the five new students is 9 years 11 months old. The average age of the remaining 4 new students is

  • 11 years 2 months

  • 13 years 6 months

  • 12 years 4 months

  • 12 years 4 months

721 Views

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65.

AD is perpendicular to the internal bisector of angle BAC of Δ ABC. DE is drawn through D and Parallel to BC to meet AC at E. If the length of AC is 12 cm, then the length of AE (in cm.) is

  • 3

  • 8

  • 4

  • 4

1100 Views

66.

The unit digit in the product (2467)153 x (341)172 is

  • 7

  • 8

  • 4

  • 4

263 Views

67.

There is a wooden sphere of radius 6 square root of 3 space cm. The surface area of the largest possible cube cut out from the sphere will be

  • 864 cm2

  • 464 square root of 3 space cm squared
  • 462 cm2

  • 462 cm2

255 Views

68.

If a + b = 1, find the value of a3 + b3 - ab - (a2 - b2)2.

  • -1

  • 1

  • 0

  • 0

164 Views

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69.

If 7 space sin squared straight theta space plus space 3 cos squared straight theta space equals space 4, then the value of tan θ is (θ is acute)

  • fraction numerator 1 over denominator square root of 3 end fraction
  • fraction numerator 1 over denominator square root of 2 end fraction
  • square root of 3
  • square root of 3
155 Views

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70.

A cylinder with base radius 8 cm and height 2cm is melted to form a cone of height 6 cm. The radius of the cone will be

  • 6 cm

  • 8 cm

  • 4 cm

  • 4 cm


B.

8 cm

Volume of cylinder = πr squared straight h space equals space straight pi space cross times space 8 space cross times space 8 space cross times 2 space equals space 128 space straight pi space cm cubed
Let the radius of the base of cone be R cm. then according to the question,
1 third πR squared straight H space equals space 128 space straight pi
rightwards double arrow space space space space space space straight R squared space cross times space 6 space equals space 128 space cross times space 3
rightwards double arrow space space space space space space straight R squared space equals space fraction numerator 128 space cross times space 3 over denominator 6 end fraction space equals space 84
rightwards double arrow space space space space space straight R space equals space square root of 64 space equals space 8 space cm

    

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