Question

A small accounting firm recently leased a new document management device (an all-in-one machine capable of printing, scanning, copying, and faxing) for three years. Reliability was a deciding factor. The company’s research found that during any given year, approximately 86% of the devices sold in one particular model required no service in a year, 9% needed one repair, 4% needed two repairs, 1% required three repairs, and none required more than three repairs in a year.

Considering this information to suggest a probability distribution for the number of repairs, find the standard deviation of the number of repairs required in a year.

		0.55 repairs.
		1.00 repairs.
		0.20 repairs.
		1.20 repairs.
		0.89 repairs.

I missed this business analysis homework problem. Please help and show step by step

Answer 1

gicn data et x be the ombe of vepoin in one eco to0 0 +0.09+0.08+o.o3

0+0.09+0.16t0.09 0.34 0.34 (o.30) , 34-0.04-0.30 0.30 = 0.544 0.55