If you mean in decimal form then it would be 15.65
<span>Decimal</span>
<span>
</span>
<span>3/2000 = 0.0015</span>
To set the equation,we can first find how much price would be raised within a year:
=500×(1+7%)
=500×1.07
As the years go by the increase would accumulate,and the equation would be:

Hope it helps!
Comment
I'm going to take a guess at this and say what you meant is 2401 = 7^(6 - 2x)
Step One
Find out the power of 7 that will equal 2401.
You could do it like this.
7^y = 2401 and just guess at some values.
y 7^y
1 7
2 49
3 7 * 7 * 7 = 343
4 7 * 7 * 7 * 7 = 2401 So the answer is 4
7^4 = 2401
Step 2
Equate the powers.
2401 = 7^(6 - 2x)
7^4 = 7^ (6 - 2x)
4 = 6 - 2x Subtract 6 from both sides.
4 - 6 = - 2x
-2 = - 2x divide by - 2
-2/-2 = x
x = 1 <<<<<<<<<<<<<answer