Engineering Quantitative Aptitude English Reasoning General Knowledge Coding Others

Quiz: Surds And Indices

To View Tricks: Login Required

Number of Questions: 25

Question: 21 -

(1000)6/1015 = ?

Options:

  1. 10

  2. None of these

  3. 100

  4. 1000

    5. Answer:

    1000
    Solution:

    (1000)6/1015

    = (1000)6 / 1015

    = (103)6/1015

    = 10(3×6)/1015

    = 1018/1015

    = (10)(18 – 15)

    = 103 = 1000

     

Question: 22 -

If 3x-y=27 and 3x+y=243,

then find the value of x.

Options:

  1. 4

  2. 2

  3. 1

  4. 3

    5. Answer:

    4
    Solution:

    3x-y=27=33<=>x-y=3... (i)

    3x+y=243=35<=>x+y=5... (ii)

    adding (i) and (ii)

    =>2x=8=>x=4

Question: 23 -

If 5a = 625, then the value of 5(a – 2) is:

Options:

  1. 5

  2. 125

  3. 625

  4. 25

    5. Answer:

    25
    Solution:

    5a = 625

    5a = 54

    a = 4

    Therefore,

    5(a – 2) = 5(4 – 2) = 52 = 25

     

Question: 24 -

What is value of M in (p/q)2M+2 = (q/p)9-M

Options:

  1. 5

  2. -7/2

  3. -11

  4. 6

    5. Answer:

    -11
    Solution:

    indices and surds

Question: 25 -

(15)3.5 × (15)x = 158

Options:

  1. 4.25

  2. 4.5

  3. 2.75

  4. 2.29

    5. Answer:

    4.5
    Solution:

    Let (15)3.5 × (15)x = 158

    Then, (15)3.5+ x = (15)8

    3.5 + x = 8

    x = (8 – 3.5)

    x = 4.5