Student: What if I am solving a problem where some of the numbers are decimals instead of fractions?

Mentor: You will need to know how to change a fraction into a decimal. That is a very useful thing to know.

Student: What about this problem, where one candidate receives one-fourth of the votes in an election, and I need to know which of the amounts below equals one-fourth?
a) 1/4
b) .30
c) 2/5
d) .25
e) a and b
f) a and d
g) c and d
h) a and c

Mentor: Well, you already know that one-fourth is the same a 1/4, so the remaining problem is to find out how to change the fraction 1/4 into a decimal, such as answers b) and d) in your problem above.

Student: How are fractions changed into decimals?

Mentor: Simply multiply the fraction by 100 and move the decimal point two spaces to the left.
You learned in the Comparing Fractions Discussion that 100 can be expressed as a fraction to make the multiplication easier, so the rest of the problem gets solved this way:

   1     100       100  
   _  X  ___   =   ___   and  100/4  = 25.
   
   4      1         4  

   Moving the decimal makes it .25

Student: OK. So the answer to my problem above is f).

Mentor: You've got it.

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