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Sub 505 Level|   Percent and Interest Problems|               
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Bunuel
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A certain telescope increases the visual range at a particular locatio 26 Nov 2015, 06:04
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E
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A certain telescope increases the visual range at a particular location from 90 kilometers to 150 kilometers. By what percent is the visual range increased by using the telescope ?

(A) 30%
(B) 33 1/2%
(C) 40%
(D) 60%
(E) 66 2/3%
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E
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A certain telescope increases the visual range at a particular locatio 26 Nov 2015, 07:45
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Original visual range = 90 km
New visual range = 150 km
Percent increase in the visual range by using the telescope
= (150-90)/90 * 100%
= 2/3 * 100%
= 66.67 %

Answer E
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A certain telescope increases the visual range at a particular locatio 26 Nov 2015, 11:59
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Same as Skywalker18

IMHO (E) - Unless there is a catch
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A certain telescope increases the visual range at a particular locatio 26 Nov 2015, 16:38
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Hi All,

Since this question asks for percent increase, we have the 'clue' that we need to use the Percent Change Formula...

Percent Change = (New - Old)/Old = Difference/Original

Since the original range is 90 and the new range is 150, we end up with....

(150-90)/90 = 60/90 = 2/3 = 66 2/3%

Final Answer:
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E

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A certain telescope increases the visual range at a particular locatio 23 Dec 2019, 18:13
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Bunuel
A certain telescope increases the visual range at a particular location from 90 kilometers to 150 kilometers. By what percent is the visual range increased by using the telescope ?

(A) 30%
(B) 33 1/2%
(C) 40%
(D) 60%
(E) 66 2/3%
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The percent increase is:

(150 - 90)/90 x 100 = 60/90 x 100 = 66 2/3%

Answer: E
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A certain telescope increases the visual range at a particular locatio 04 Sep 2021, 11:28
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Pretty Easy Question,
Old range is 90 kms & New range is 150 kms
Percent increase= ((New - old) / old)*100
(150-90)/90 * 100%
2/3 * 100%
66.67 %
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Sneha2021
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A certain telescope increases the visual range at a particular locatio 29 Oct 2021, 11:21
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The fastest approach is to estimate the answer using options
Let's start with D because we need a value greater than 50% (50% of 90 is 45), so we need a value greater than 50%
60% increase of 90 will be around 54 and difference is 60 (150-90), so ans must be greater than 60%.
Select E
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A certain telescope increases the visual range at a particular locatio 27 May 2023, 02:18
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To calculate the percent increase in visual range, we need to find the difference between the initial range and the increased range, and then express that difference as a percentage of the initial range.

Initial visual range: 90 kilometers
Increased visual range: 150 kilometers

Difference in visual range: 150 km - 90 km = 60 km

Now, we'll calculate the percentage increase:
Percentage increase = (Difference / Initial range) * 100

Percentage increase = (60 km / 90 km) * 100 ≈ 66.67%

Therefore, the visual range is increased by approximately 66 2/3%, which corresponds to option (E) in the given choices.
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