Surds and Indices

Surds and Indices

Congratulations - you have completed Surds and Indices.

You scored %%SCORE%% out of %%TOTAL%%.

Your performance has been rated as %%RATING%%


Your answers are highlighted below.
Question 1
(17)^3.5 x (17)^? = 17^8
A
2.29
B
2.75
C
4.25
D
4.5
Question 1 Explanation: 
Let (17)^3.5 x (17)^x = 17^8. Then, (17)^3.5 + x = 17^8. 3.5 + x = 8 ==> x = (8 - 3.5) ==> x = 4.5
Question 2
Given that 100.48 = x, 100.70 = y and xz = y2, then the value of z is close to:
A
1.45
B
1.88
C
2.9
D
3.7
Question 2 Explanation: 
x^z = y^2 10^(0.48z) = 10^(2 x 0.70) = 10^(1.40) 0.48z = 1.40 z =140/48 =35/12 =2.9 (approx.)
Question 3
If 5^a = 3125, then the value of 5^(a - 3) is:
A
25
B
125
C
625
D
1625
Question 3 Explanation: 
5^a = 3125 5^a = 5^5 a = 5. 5^(a - 3) = 5^(5 - 3) = 5^2 = 2^5.
Question 4
If 3^(x - y) = 27 and 3^(x + y) = 243, then x is equal to:
A
0
B
2
C
4
D
6
Question 4 Explanation: 
3^(x - y) = 27 = 3^3 x - y = 3 ....(i) 3^(x + y) = 243 = 3^5 x + y = 5 ....(ii) On solving (i) and (ii), we get x = 4.
Question 5
(256)0.16 x (256)0.09 = ?
A
4
B
16
C
64
D
256.25
Question 5 Explanation: 
(256)^0.16 x (256)^0.09 = (256)^(0.16 + 0.09) ==> (256)^0.25b==> (256)^(25/100) ==> 4^(4*(1/4))1/4)=4
Once you are finished, click the button below. Any items you have not completed will be marked incorrect. Get Results
There are 5 questions to complete.

Leave a Reply

Your email address will not be published. Required fields are marked *