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 :

= 0.625
Answer:
3
Step-by-step explanation:
P is the in-center
⇒PA=PE=PD because they are in-radius of the in-circle
We know that, tangent segments drawn from a point outside the circle are always equal in length
⇒DK=EK=7.2
In right triangle PKE,
using Pythagoras' Theorem : 
⇒
⇒
⇒
⇒
Therefore, 
I believe its 180.
I have seen this question before and the amount of girls was 220, so 400-220 is 180
Hope this helps :)