Aptitude - Surds and Indices - Discussion
Discussion Forum : Surds and Indices - General Questions (Q.No. 6)
6.
(256)0.16 x (256)0.09 = ?
Answer: Option
Explanation:
(256)0.16 x (256)0.09 = (256)(0.16 + 0.09)
= (256)0.25
= (256)(25/100)
= (256)(1/4)
= (44)(1/4)
= 44(1/4)
= 41
= 4
Discussion:
16 comments Page 1 of 2.
Vishnu said:
7 years ago
I think the answer is 64 because 4 th root of 256 is = 64 So answer is 64.
(2)
Shree said:
7 years ago
I too agree it is 64.
(2)
Priya said:
2 years ago
(256)0.16 x (256)0.09.
= (256)^(0.16 + 0.09)
= (256)^0.25
= (256)^(0.25/100)
= (256)^25/100
= (256)^(1/4)
= (16²)^(1/4)
16² can be written as (4²)².
= (4⁴)^1/4.
= 4^4×1/4.
Cancellation of powers we get answer as 4.
Another Method :
= (256)^0.25.
= (16²)^0.25 --> ( multiplication of powers 2×0.25),
= (16)^0.50,
= (4²)^0.50 --> ( multiplication of powers 2×0.50)
= 4¹.
= 4.
= (256)^(0.16 + 0.09)
= (256)^0.25
= (256)^(0.25/100)
= (256)^25/100
= (256)^(1/4)
= (16²)^(1/4)
16² can be written as (4²)².
= (4⁴)^1/4.
= 4^4×1/4.
Cancellation of powers we get answer as 4.
Another Method :
= (256)^0.25.
= (16²)^0.25 --> ( multiplication of powers 2×0.25),
= (16)^0.50,
= (4²)^0.50 --> ( multiplication of powers 2×0.50)
= 4¹.
= 4.
(1)
Stacy said:
2 years ago
Why do we divide it by 100? Anyone, please explain to me.
(1)
Prasanthi said:
1 decade ago
(4^4)^16/100*(14^4)^9/100.
= (4)^16/25*(4)^9/25.
= (4)^25/25.
= 4.
= (4)^16/25*(4)^9/25.
= (4)^25/25.
= 4.
Gil said:
1 decade ago
Where did you get number of 100?
Sairam said:
1 decade ago
@Gil, 0.25 can be written as 25/100.
Angel said:
9 years ago
Nice explanation @Prasanthi.
Golusingh said:
9 years ago
Very well explained. Thanks.
Gagan Deep kaur said:
9 years ago
Nice explanation. Thank you all.
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