Q:

why mdpi devices not acessing images from drawable folder

I am developing a game and i want to use only 1 set of images as images are quite big in size and using different images for different device configuration will increase my application(which is already around 10Mb).  But i am not sure where to put these images .  if i put the images in hdpi folder mdpi devices not working and vice versa .  i also tried putting images in /drawable folder but that also not working. 
I am taking high density images and scaling them down. 
Also i want to know about the application deployment like if i put different images in different folder; does only that folder which is compatible to device is used while installation or all the folders are added.  how it actually works.  

A:

You should store your images under drawable-nodpi folder. 

Also i want to know about the application deployment like if i put
  different images in different folder; does only that folder which is
  compatible to device is used while installation or all the folders are
  added.  how it actually works. 

All images are installed, but only those are taken at runtime, which fit best to the current device configuration.  Images from drawable-nodpi are density independent and can be used on every device as they are. 