# Easy Algebra Solved QuestionAptitude Discussion

 Q. On a scale that measures the intensity of a certain phenomenon, a reading of $n+1$ corresponds to an intensity that is 10 times the intensity corresponding to a reading of $n$. On that scale, the intensity corresponding to a reading of 8 is how many times as great as the intensity corresponding to a reading of 3?
 ✖ A. $500$ ✖ B. $3^5$ ✔ C. $10^5$ ✖ D. $50$

Solution:
Option(C) is correct

$n=8$ implies $10^8$

$n=3$ implies $10^3$

Hence, $10^8 /10^3= 10^5$ will be required.

Edit: For a solution with a different approach, visit KARTIK's comment.

## (6) Comment(s)

SWARUP
()

ANS 10^5

N------>Let ---> X

N+1-------------> 10X

FOR 3 ---LET--> Y

4------------>10Y

5------------->100Y

8------------>10^5Y

KARTIK
()

Question is right but i guess explanation is bit confusing.

Suppose reading corresponding 1 $= x$ i.e any number reading corresponding to $1+1$ i.e $2 = 10x$

For $3 = 10*10x$

For $8 = 10^7x$

Divide reading corresponding to 8 by reading corresponding to $3 = 10^5$

Abhishek
()

lets say at a reding of $n$ the intesity be $x$. than at next reading comes out to be 10 times of previous intesity...that is $10*x$.

now u dont need to add these eaquation like this :

n--->x
(n+1)--> 10*x
-----------------
2n+1 ----> 11x

u cant add them like this ...for instance let

$n=1$ than intensity be $x$

$n=2$ than intensity will be $10*x$ and if u add them according to above than it turns out to be

$n=3$ intensity will be $11x$...which is not true

bcause at $n= 3$ the intensity is 10 times of the

previous one which is $n=2$-->$10x$. thus it will be $100*x$.

Rahul
()

as you are saying for reading 1 had a value of 10 but how can take it as it is 10.

it is giving as equation :-

$n+1 = 10 \times n$

so by putting 8 and 5, i am getting 50 as answer.

Barun
()

well it's not that difficult.. It basically tells us that each number on the scale is 10 times the intensity of the previous number.

For ex. if a reading of 1 had a value of 10, then a reading of 2 would have a value of $10*10$, a reading of 3 would have a value of $10*10*10$ and so on.

So, if we want to compare a reading of 8 to a reading of 3, we've gone up by 5 ranks of intensity, which means we're multiplying by $10*10*10*10*10 = 10^5$.

Animesh
()

don't really understand the question...