Answer:
50 soldiers must be transferred elsewhere.
Step-by-step explanation:
We solve this question by proportions, using a rule of three.
As the number of soldiers decrease, the provisions last for more time. This means that the measures are inversely proportional, and we have an inverse rule of three, using line multiplication, instead of cross.
30 days of provisions - 200 soldiers
40 days of provisions - x soldiers
Simplifying by 40
The provisions will last for 40 days with 150 soldiers, which means that 200 - 150 = 50 soldiers must be transferred elsewhere.