Answer:
0.625
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 :
![$(0.4 * 0.25)/((0.6 *0.1)+(0.4 * 0.25))$](https://img.qammunity.org/2022/formulas/mathematics/college/lpcmxnuukzzcnz8fedffe6i6xqdcysyvc2.png)
= 0.625