number line

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number line

by sumasajja » Thu Jul 28, 2011 5:36 pm
a 12 inch ruler is marked off in sixteenth of an inch. what is the distance,in inches , from the zero mark to the 111th mark after the zero mark?
a]6 1/4
b]6 15/16
c]7 3/4
d]9 1/4
e]11 1/16
answer isb
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by jaymw » Thu Jul 28, 2011 6:32 pm
a 12 inch ruler is marked off in sixteenth of an inch. what is the distance,in inches , from the zero mark to the 111th mark after the zero mark?
a]6 1/4
b]6 15/16
c]7 3/4
d]9 1/4
e]11 1/16
answer isb
For this problem we have to calculate the distance between the 111th mark and zero. Therefore, knowing where exactly on the ruler the 111th mark lies will suffice to answer the question.

The first mark will be at 1/16 of an inch, the second mark will be at 2/16 of an inch, and so on.

The 111th mark will therefore be at 111/16 of an inch.

Since that isn't one of the answers, we have to rewrite it as a mixed number:

111:16 = ?

Considering that 16*7=112, we know that 111:16 must be marginally less than 7, therefore only answer choice B can be correct.

The information about the ruler being 12 inches long is completely irrelevant, it could also be 1000 inches long.

What's the source of this problem?

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by ntamhane » Thu Jul 28, 2011 6:40 pm
The answer's B

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by sumasajja » Thu Jul 28, 2011 8:19 pm
jaymw wrote:
a 12 inch ruler is marked off in sixteenth of an inch. what is the distance,in inches , from the zero mark to the 111th mark after the zero mark?
a]6 1/4
b]6 15/16
c]7 3/4
d]9 1/4
e]11 1/16
answer isb
For this problem we have to calculate the distance between the 111th mark and zero. Therefore, knowing where exactly on the ruler the 111th mark lies will suffice to answer the question.

The first mark will be at 1/16 of an inch, the second mark will be at 2/16 of an inch, and so on.

The 111th mark will therefore be at 111/16 of an inch.

Since that isn't one of the answers, we have to rewrite it as a mixed number:

111:16 = ?

Considering that 16*7=112, we know that 111:16 must be marginally less than 7, therefore only answer choice B can be correct.

The information about the ruler being 12 inches long is completely irrelevant, it could also be 1000 inches long.

What's the source of this problem?
it is from peterson's book

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by jaymw » Thu Jul 28, 2011 8:28 pm
sumasajja wrote:
jaymw wrote:
a 12 inch ruler is marked off in sixteenth of an inch. what is the distance,in inches , from the zero mark to the 111th mark after the zero mark?
a]6 1/4
b]6 15/16
c]7 3/4
d]9 1/4
e]11 1/16
answer isb
For this problem we have to calculate the distance between the 111th mark and zero. Therefore, knowing where exactly on the ruler the 111th mark lies will suffice to answer the question.

The first mark will be at 1/16 of an inch, the second mark will be at 2/16 of an inch, and so on.

The 111th mark will therefore be at 111/16 of an inch.

Since that isn't one of the answers, we have to rewrite it as a mixed number:

111:16 = ?

Considering that 16*7=112, we know that 111:16 must be marginally less than 7, therefore only answer choice B can be correct.

The information about the ruler being 12 inches long is completely irrelevant, it could also be 1000 inches long.

What's the source of this problem?
it is from peterson's book
I guess the thing that is a bit strange about this question is that unneccessary information is given. This usually doesn't happen with "high-quality" questions.