The expression 3P2 can also be read as "permutation of 3 taken 2". This represents the number of ways in which the 3 items are arranged with the emphasis on the arrangement of the first two other items.
Well 1/3 for savings means that you save 1/3*4500 or 1500 dollars.
You then have $3000 left. Of this if you spend 50% on food, you spend 0.5*3000 or 1500 dollars on food.
The acute angle inside the triangle is 57 degrees. The one labeled “1” is 123 degrees.
