Sharp EL-531LH - Using the X -1 Key

18 Mastering the Calculator using the Sharp EL-531LH
Example
Find
Using the calculator the key strokes are:
and the display will show 8 ⎡ 71 ⎡ 72 which is read as
Note if you now press the display will read 647 ⎡ 72. So this key turns a mixed
fraction into an improper fraction.
If you press the key a second time the decimal equivalent is displayed,
i.e. 8.9861111
6. Using the x
-1
key
8
1
9
---
63
7
2
--
----
+
8
71
7
2
--
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