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To find how much time it would take Sylvester to walk the path,
organize the information to form a proportion.
Now solve the proportion.
1040 t153,600 Cross multiply.
t 148 Simplify.
It would take Sylvester about 148 seconds to walk the inside path.
Method 2:Solve a Simpler Problem
As you did for Method 1, make a rough
sketch that shows the important information.
Your sketch will reveal that the outside path
is a total of 8(10 feet), or 80 feet, longer than
the inside path.
To solve this problem, you can first answer
the simpler question: “How long does it take
Sylvester to walk 80 feet?”
Once you have this answer, you can subtract
it from the 160 seconds it takes to walk the
outside path. This will be the time it would
take Sylvester to walk the inside path.
To determine that Sylvester’s walking rate
is 6.5 feet per second, divide 1040 feet (the
length of the outside path) by 160 seconds
(the length of time it took Sylvester to walk
the outside path).
At a rate of 6.5 feet per second, it would
take Sylvester 80 ÷ 6.5, or about 12, seconds
to walk 80 feet. Taking these 12 seconds off
his outside path’s time of 160 seconds, you
find that it would take him about 148 seconds
to walk the inside path.
Check to make sure your answer makes sense.
The same solution was found two different ways,
so you can feel confident that it is correct.
time to walk outside path
perimeter of outside path
time to walk inside path
perimeter of inside path
160 sec
1040 ft
tsec
960 ft
160
1040
t
960
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Lesson 8-14 for exercise sets.
240 ft
10 ft 10 ft
10 ft 10 ft
10 ft
10 ft
10 ft
10 ft
240 ft
