counting zeros in a terminating decimal

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counting zeros in a terminating decimal

by Amrabdelnaby » Thu Jan 07, 2016 4:12 am
Hello Pros,

in counting zero digits in a terminating decimal, do I also count the zero on the left of the decimal?

for example would it be proper to say at 1/4 has one zero digit since it is equal to 0.25? or do we only count the zeros on the right of the decimal and hence we would consider 1/4 to have non zero digits?

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by MartyMurray » Thu Jan 07, 2016 8:32 am
I think that the key thing is not some "rule" for which zeros to count. The key thing is to notice what a GMAT question is asking.

I am sure that GMAT questions you see on the test will clearly state or somehow make clear what you need to count or not count. The creators are not going to count on you knowing some "rule" for which zeros to count. That would be ridiculous.

This thing is meant to gauge one's problem solving skills, vision and other things related to effectively handling business school curricula, not whether one knows minutia such as which zeros to count.

It's one thing to know that 0 is an even integer, or to remember that one could multiply by zero and get a certain answer. Those things are key foundational concepts and logical conclusions. It's another to know some freaky little, rarely discussed thing such as which zeros to count.
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by [email protected] » Thu Jan 07, 2016 12:02 pm
Hi Amrabdelnaby,

When 'counting 0s', you're supposed to ignore the 0s to the left of the decimal point.

Since....
0.5
00.5
000.5
0000.5

...are all the same number, those 0s are all redundant/unnecessary.

In that same way....

.5
.50
.500
.5000

...since these values are all the same number, those extra 0s (to the right of the 5) are all redundant/unnecessary.

The types of questions that you're referring to will have a 'string' of 0s that eventually ends in a non-0 number

For example, .0004

This example is a terminating decimal that has three 0s.

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by Matt@VeritasPrep » Fri Jan 08, 2016 12:37 pm
You can ignore the zero to the left unless the problem explicitly tells you to count it.