How to solve this type of Q( SET 5 Q 15)

saurabh_1922@yahoo.co.in

Q15:
Which of the following fractions has a decimal equivalent that is a terminating decimal?
A. 10/189
B. 15/196
C. 16/225
D. 25/144
E. 39/128

How to solve thesetype q without calculating manually.
Any tricks?

answer · Guest

saurabh_1922@yahoo.co.in · Posted: Fri Sep 14, 2007 8:32 am Post subject:

That works Smile

Thanks,
saurabh

camitava · Posted: Sat Sep 15, 2007 12:12 am Post subject:

Sorry friends! I am not even clear with the question as well as the approach described by answer. Can you pls explain this more clearly so that it will be easy for me to understand. Looking for ur explanation.

saurabh_1922@yahoo.co.in · Posted: Sat Sep 15, 2007 4:26 am Post subject:

Amitava, the question is- which fraction will give a terminating decimal.
For example- 1/2 = .5 which is terminating
1/3 =.333333 which is not terminating.
I believe now will understand the approach as well.
Let us know

camitava · Posted: Sat Sep 15, 2007 4:44 am Post subject:

Yop! Thanks Saurab. Got it. But now going back to ur question, my next question is - Will you sit to find which denominator is coming in the form of 2^m5^n? To me, it appears quite time taking.

saurabh_1922@yahoo.co.in · Posted: Sat Sep 15, 2007 5:47 am Post subject:

No amitava.
you just need to factorise the denominator.
I dont think its time taking.
For ex- if denominator is 224 its in theform 2(5 times) * 7.
So you know which form it belongs to