Integer which is Multiplied by 9 when moving Last Digit to First/Decimal Expansion
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Lemma for Integer which is Multiplied by 9 when moving Last Digit to First
- $\dfrac 9 {89} = 0 \cdotp \dot 10112 \, 35955 \, 05617 \, 97752 \, 80898 \, 87640 \, 44943 \, 82022 \, 471 \dot 9$
Proof
From Reciprocal of 89 we have:
- $\dfrac 1 {89} = 0 \cdotp \dot 01123 \, 59550 \, 56179 \, 77528 \, 08988 \, 76404 \, 49438 \, 20224 \, 719 \dot 1$
Hence:
0.01123 59550 56179 77528 08988 76404 49438 20224 7191 x 9 ------------------------------------------------------ 0.10112 35955 05617 97752 80898 87640 44943 82022 4719 11235 844 5 51786 6427 88776 53 44 83371 2246 18
The lowest line is the carry digit.
As there is no overall carry digit on the left of the product, it follows that:
- $\dfrac 9 {89} = 0 \cdotp \dot 10112 \, 35955 \, 05617 \, 97752 \, 80898 \, 87640 \, 44943 \, 82022 \, 471 \dot 9$
$\blacksquare$