Question 957386
<pre>
There are 7 red marbles + 4 blue marbles = 11 marbles.

The probability of choosing a red marble is

7 out of 11

"Out of" means "over", so that's

7 over 11 which is {{{7/11}}}

That would be the answer but the instructions say
</pre>
giving your answer to 2 decimal places
<pre>
So we change {{{7/11}}} to a decimal:

We divide the bottom number 11 into 7, but instead of
7 we write it as 7.000, one more decimal place than 2



  <u>  .636</u>
11)7.000
   <u>6 6</u>
     40
     <u>33</u>
      70
      <u>66</u>
       4
      
Since the third decimal digit is 6, 
and 6 is "5 or more", we round the
second decimal place 3 up to 4, and
eliminate the third decimal digit 6:

Answer = .64

We like to put a 0 in front, so it
would be better to write the answer
as  0.64

The big 0 is to "protect" the tiny decimal point. :)

Answer = 0.64

Edwin</pre>