Are these formulas correct? Mean deviation = 4/5 * Quartile Deviation, ...

Mean deviation=4/5*Quartile Deviation
Quartile Deviation=2/3*Standard Deviation

medison said:

Mean deviation=4/5*Quartile Deviation
Quartile Deviation=2/3*Standard Deviation
Mean deviation=4/5*Quartile Deavition

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No. The first and third statement are the same, so one of them can be dropped. The other two come down to
Quartile Deviation=2/3*Standard Deviation=5/4*MeanDeviation
Let our sample space be
1, 1, 2, 2, 3, 3, 4, 4,
What is the Mean deviation? The Quartile Deviation? The Standard Deviation?