1. we know she needs 3 packs of biscuits
2. Shop A you only need to pay for 2 packs
3. Shop B you only need to pay for 2 packs
4. Shop C you need to pay for all three
5. so we know C is out of the option.
![1.90 \times 2](https://tex.z-dn.net/?f=1.90%20%5Ctimes%202)
so shop A and B will cost the least
Number of proper subsets = 2^number of elements- 1
= 2^n - 1
No of elements = 4
2^4-1 = 16-1 = 15
Answer:
-20, -13, -3 0, 19
Step-by-step explanation:
With negative the higher the number the lower the value
10 or 25 and a lot more pretty much anything that ends with 0 or 5