The Ambell Company uses batteries from two different manufacturers. Historically, 70% of the batteries are from manufacturer 1, and 90% of these batteries last for over 40 hours. Only 75% of the batteries from manufacturer 2 last for over 40 hours. A battery in a critical tool fails at 32 hours. What is the probability it was from manufacturer 1?

Respuesta :

Answer:

0.625

Step-by-step explanation:

Given :

Ambell company uses or procures batteries from two manufacturers.

The life of a battery in critical tool is at = 32 hours

Ambell uses 70% of its batteries from manufacturer 1 and out of that 90% batteries lasts for about 40 hours.

Similarly, 75% of the batteries procured from the manufacturer 2 lasts for about 40 hours.

Therefore, the probability that a battery is form manufacturer 1 is :

[tex]$\frac{0.4 \times 0.25}{(0.6 \times0.1)+(0.4 \times 0.25)}$[/tex]

= 0.625