Expert: Sherry Wallin - 3/15/2009

Question
QUESTION: Hello:

I read the following in an old business mathematics textbook:
"Express 13 mills as a decimal part of $1.00."

I can determine the answer as follows: There are 1000 mills in or per $1.00. 13 mills divided by 1000 mills/$1.00 equals $0.013, the answer.

My question is as follows: What does "...as a decimal part of $1.00" indicate or represent from "Express 13 mills as a decimal part of $1.00."?

I thank you for your reply."


ANSWER: Kenneth~
    "as a decimal part of $1.00" means the mills divided by $1.00. Remember every dollar has 100 cents so if there are 1000 mills in a dollar there are 10 mills in every cent. Here's the ratio:
10mils/1 cent = 13 mils/ x cents, now solve for x by cross multiplying
getting 10x = 13 and then x = 13/10 = 1.3, that is there are 1.3 cents for every 13 mils and then change 1.3 cents back into a dollar = $.013 or I could have just as well said change 1.3 cents back into a decimal and arrived at the same answer .013 per 100. Does this make sense? Hope so.

Math Prof

---------- FOLLOW-UP ----------

QUESTION: Hello Math Prof:

I want to thank you for the reply.

I still need some clarification. Here is what I have determined, but I'm not whether or not some of this information is correct.

Does "a decimal that is "a part of $1.00" represent any of the following:

These are decimals that are parts of $1.00.

If carried out to two decimal places, the decimal part of $1.00 would be from $0.01 to $0.99.

If carried out to three decimal places, the decimal part would be from $0.001 to $0.099 or something like these.

Are these decimals "parts" of $1.00 because they have a value less than $1.00. Or does "a decimal part of $1.00" indicate any decimal that is less than $1.00 with a dollar sign in front of the decimal.

$0.25 is a decimal part of $1.00 + $0.75 is a decimal part of $1.00. These two decimals equal $1.00.

I thank you for your follow-up reply.



ANSWER: Hi Kenneth~
    Anything positive and smaller than $1.00 can be thought of as a decimal part of $1.00. Decimal part most often refers to the fractional part or the part that is 0< x < 1.

These are decimals that are parts of $1.00?   Yes

If carried out to two decimal places, the decimal part of $1.00 would be from $0.01 to $0.99.  Yes

If carried out to three decimal places, the decimal part would be from $0.001 to $0.099 or something like these. No from .001 to .99

Are these decimals "parts" of $1.00 because they have a value less than $1.00?  Yes

Or does "a decimal part of $1.00" indicate any decimal that is less than $1.00 with a dollar sign in front of the decimal.  not necessarily

Hope this clears things a bit for you.

Math Prof

---------- FOLLOW-UP ----------

QUESTION: Hello Math Prof:

I cannot thank you enough for the reply. It was indeed helpful!

Would the following make sense: Express 13 mills as a decimal part of $1.50, or as a decimal part of $0.50, or as a decimal part of $0.10?

I thank you for your help and assistance.

Answer
Hi Kenneth~
    Technically you could speak about decimal parts like that but it loses it's purpose. Percents mean x parts out of 100 just like we generally speak of mills of a dollar which is 100 cents. If you spoke of 13 mils out of %1.50 that's the same as 8.67 mils out of $1.00 (or .00867) and 13 mils out of $.50 is the same as 26 mils out of (or decimal part of or .026 mils) $1.00.

Math Prof

BTW your welcome