What numbers can you make using 3, 5 and 7? You can make 357 and 537. What others?

Q. What is the biggest two-digit number you can make using the digits 2 and 7 without repeating any digit?

Q. You can given one hundred 1 Ω resistors. What is the smallest and largest resistance you can make in a circuit using these?

Q. What are the smallest and greatest numbers that you can make with the digits 6, 3, 9 and 8?

Q. You can make 24 four-digit numbers by using 4,3,2 and 1 without repeating any digits.

Q. Objects have qualities which make them desirable to others. Can you think of some objects (a car, a phone, a dress…) and say what qualities make one object more desirable than another? Imagine you were trying to sell an object: what qualities would you emphasise?