Answer:
a) (10×13) + 55 b) 185 Nu c)-75 or -205 (unsure of instruction)
Explanation:
a) He spends 10 Nu a day for 13 days, meaning he has spent 10×13 Nu. He originally had this amount, plus the 55 he ends up with. This means he began with (10×13) + 55.
b) This can then be solved using BODMAS (or PEMDAS, whatever you call the order of operations).
We begin with the multiplication, which turns the expression to 130+55. We then move to addition, giving a final result of 185.
c) For this one, I'm not sure if it is if he did that from the beginning or from now, so I've done both.
If it's from the beginning, you would use 185-(20×13) to solve this. This gives 185-260, which solves to -75.
If it's from the point of 55 Nu, you would use 55-(20×13), which gives 55-260. This solves to -205.
**You may wish to revise writing integer expressions. I'm always happy to help!