Question

The value of an investment increases by x% during January and decreases by y% during February. If the value of the investment is the same at the end of February as at the beginning of January, what is y in terms of x ?

Answer 1

y in terms of x would be:

y = 100 - 10,000 / (100 +x)

Step-by-step explanation:

Let us assume the investment amount is 100

And let x is equal to 25 and y is equal to 20

So, there is increase in January

= 100 + 25% × 100

= 100 + 25

= 125

In order to decrease, it is to be back down to 100 in February, y =20

= 125 - 20% × 125

= 125 - 25

= 100

Therefore, in order to check that the value of y is correct or not, which we assumed. We will plug

x = 25 into the equations:

= 100 - 10,000 / (100 + x)

= 100 - 10,000 / (100 + 25)

= 100 - 10,000 / 125

= 100 -80

= 20

Therefore, this equation is right.

Note: Options are not given so providing the direct answer.