Question

60 = 5(1.07)^x

Answer 1

Given:

The given equation is

$60=5(1.07)^x$

To find:

The initial value and growth/decay factor.

Solution:

The general exponential growth/decay model is

$y=a(1+r)^x$     ...(i)

where, a is initial value, if r>0, then |r| is growth factor, if r<0, then |r| is decay factor and x is time.

We have,

$60=5(1.07)^x$

It can be written as

$60=5(1+0.07)^x$        ...(ii)

On comparing (i) and (ii), we get

$a=5\text{ and }r=0.07$

Here, initial value is 5 and growth factor is 0.07, i.e., 7%.

Therefore, the correct option for first question is d and correct option for second question is a.