Question 344165
Let {{{x}}} = length of the planned trip in miles
The 1st day he hiked {{{x/2}}} miles
The remaining distance is {{{x/2}}} miles
On the 3rd day, he hiked half of that, or
{{{(1/2)*(x/2) = x/4}}} miles
So far he has hiked {{{x/2 + x/4 = (3x)/4}}} miles
There are {{{x/4}}} miles left
On the 4th day, he hiked {{{3}}} miles
Reading carefully, the problem is telling me that
the 3 miles he traveled on day 4 was 1/5 of the
{{{x/4}}} miles left , so
{{{3 = (1/5)*(x/4)}}}
{{{3 = (1/20)*x}}}
{{{x = 60}}} miles is the length of the planned trip
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Now, going back over the problem:
The 1st day he hiked {{{x/2 = 30}}} miles
On the 3rd day, he hiked half of that, or
{{{(1/2)*30 = 15}}} miles
So far he has hiked {{{30 + 15 = 45}}} miles
and there are {{{x/4 = 15}}} miles left
On the 4th day he hiked {{{3}}} miles which is 
{{{1/5}}} of the miles left, or {{{(1/5)*15 = 3}}}
So, he hiked {{{30 + 15 + 3 = 48}}} of the
{{{60}}} mile planned trip