Answer: 
Step-by-step explanation:
Given: A tourist first walked 17km with a speed of v km/h.
Since 
therefore, 
Let
be the time he walked with speed v.
then 
Also he hiked 12 km uphill with the speed that was 2 km/hour less than his original speed.
Let
be the time he hiked 12 km,
Then 
The total time for the whole trip is given by:-

Substitute the values of
and
in the equation, we get

Irrational due to the negative sign
There are multiple answers to this question
Answers: 3.161, 3.162, 3.163, 3.164, 3.165, 3.166, 3.167, 3.168, 3.169
(You can just pick one)
Reason: just look at the place numbers. The number has to be between 3.16 and 3.17. So go to the next place value which is the thousandths place. 3.161-3.169 all are between since they have a 6 in the hundredths place, but does not go over 1.17