There are a couple of different approaches you can use for this. Here's one.
1. Determine how many digits repeat. (There is just one repeating digit.)
2. Call your number x. Multiply x by 10 to the power of the number of digits found in step 1.

3. Subtract the original number, then solve for x.

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If you recognize that 0.333... (repeating) is 1/3, then you know that 0.0333... (repeating) is 1/10×1/3 = 1/30. Add that to 0.8 = 4/5 and you get
... 4/5 + 1/30 = 24/30 + 1/30 = 25/30 = 5/6
Answer:
(a) 36.36%
(b) 0.36%
(c) 0.06%
Step-by-step explanation:
Given that the time intervals measured with a stopwatch have an uncertainty of about 0.2 s.
We want to know what is the percent uncertainty of a hand-timed measurement of:
(a) 5.5 s
Percentage = (0.2/5.5) × 100
≈ 36.36%
(b) 55 s
Percentage = (0.2/55)×100
≈ 0.36%
(c) 5.5 min
5.5 min = 5.5 × 60 s
= 330 s
Percentage = (0.2/330)×100
≈ 0.06%
Greater than since 24/4 is 6