Fix some documentation examples involving the repr of a float.

Doc/tutorial/floatingpoint.rst

@@ -115,7 +115,7 @@ Another consequence is that since 0.1 is not exactly 1/10, summing ten values of
    ...     sum += 0.1
    ...
    >>> sum
-   0.99999999999999989
+   0.9999999999999999
 
 Binary floating-point arithmetic holds many surprises like this.  The problem
 with "0.1" is explained in precise detail below, in the "Representation Error"

Doc/tutorial/inputoutput.rst

@@ -49,10 +49,10 @@ Some examples::
    'Hello, world.'
    >>> repr(s)
    "'Hello, world.'"
-   >>> str(0.1)
-   '0.1'
-   >>> repr(0.1)
-   '0.10000000000000001'
+   >>> str(1.0/7.0)
+   '0.142857142857'
+   >>> repr(1.0/7.0)
+   '0.14285714285714285'
    >>> x = 10 * 3.25
    >>> y = 200 * 200
    >>> s = 'The value of x is ' + repr(x) + ', and y is ' + repr(y) + '...'

Doc/tutorial/stdlib2.rst

@@ -362,10 +362,13 @@ results in decimal floating point and binary floating point. The difference
 becomes significant if the results are rounded to the nearest cent::
 
    >>> from decimal import *
-   >>> Decimal('0.70') * Decimal('1.05')
+   >>> x = Decimal('0.70') * Decimal('1.05')
+   >>> x
    Decimal('0.7350')
-   >>> .70 * 1.05
-   0.73499999999999999
+   >>> x.quantize(Decimal('0.01'))  # round to nearest cent
+   Decimal('0.74')
+   >>> round(.70 * 1.05, 2)         # same calculation with floats
+   0.73
 
 The :class:`Decimal` result keeps a trailing zero, automatically inferring four
 place significance from multiplicands with two place significance.  Decimal