Homework Help: Math 115

Posted by blondie on Wednesday, December 5, 2007 at 1:45am.

Every fraction has a decimal equivalent that either terminates (for example,1/4=0.25 ) or repeats (for example,2/9=0.2 ). Work with a group to discover which fractions have terminating decimals and which have repeating decimals. You may assume that the numerator of each fraction you consider is and focus your attention on the denominator. As you complete the table below, you will find that the key to this question lies with the prime factorization of the denominator.
1/2
1/3
1/4
1/5
1/6
1/7
1/8
1/9
1/10
1/11
1/12

State a general rule describing which fractions have decimal forms that terminate and which have decimal forms that repeat.
Now test your rule on at least three new fractions. That is, be able to predict whether a fraction such as or has a terminating decimal or a repeating decimal. Then confirm your prediction.

Math 115 - drwls, Wednesday, December 5, 2007 at 2:08am
You posted this questin twice.
Math 115 - Cindy, Tuesday, June 17, 2008 at 9:06pm
1/2=0.5
1/3=0.333333333333333
1/4=0.25
1/5=0.2
1/6=0.166666666666667
1/7=0.142857142857143
1/8=0.125
1/9=0.111111111111111
1/10=0.1
1/11=0.090909090909091
1/12=0.083333333333333
Math 115 - Cindy, Tuesday, June 17, 2008 at 9:09pm
1/2=0.5
1/3=0.333333333333333
1/4=0.25
1/5=0.2
1/6=0.166666666666667
1/7=0.142857142857143
1/8=0.125
1/9=0.111111111111111
1/10=0.1
1/11=0.090909090909091
1/12=0.083333333333333
fractions with denominators of 3,6,7,9,11,12 (or multiples of these numbers) have decimal forms that repeat, while fractions with denominators of 2,4,5,8,10 (or multiples of these numbers)have decimal forms that terminate.

i predict that 1/25 has a terminating decimal
reason: 25 is a multiple of 5, which has a terminating decimal
1/25=.04 correct
Any power of 10 only has 2 and 5 as prime factors. So if the reduced fraction has a denominator with factors other than 2 or 5, those factors will always be there, and there will be no way to get the fraction expressed with a power of 10 for the denominator. So in conclusion: if the reduced form of the fraction has only 2 and 5 for prime factors in its denominator, then the decimal terminates.

Answer this Question

Related Questions

Math 115 - Every fraction has a decimal equivalent that either terminates (for ...
math - ACTIVITY 12: TERMINATE OR REPEAT? Every fraction has a decimal equivalent...
Math - Write 8/25 in Decimal (use the prime factorization of the denominator and...
math - how can you find an equivalent of a fraction for example 15/24 and the ...
Math - I need the steps and an example for chaning a fraction to a percent. I ...
math 6 grade - When the LCM of two numbers the same as one of the numbers?Use an...
math - how do you turn fractions into decimals? what do you do with the ...
Math - You earned a $25 gift card by working in Apangea and have purchased four ...
grade 7 math - I really need someone to explain how to change a decimal to a ...
Math - How would I find an equivalent fraction if I only have one fractions. For...

For Further Reading

First Name:
School Subject:
Answer: