Lesson 3: Smallest Number of Bits Required to Hold a Number

Question 1: Bitcoin cannot exceed 21 million in total supply and it has 8 decimals. What is the smallest uint size that can be used to contain it? Give your answer as the type, for example uint256.

Question 2: What is the smallest uint required to hold 1 billion Ether? 1 Ether is measured as 10**18.

Question 3: USDC requires 6 decimals to store, so one dollar of USDC is 10**6. What is the smallest uint needed to hold 1 trillion USDC?

Question 4: What is the smallest uint required to store 30 days in seconds?

Question 5: Your application has a userid. The world population is 7 billion people, but each person might have up to 10 accounts. What is the smallest uint needed that can safely count every userid?