Number Substitution( Week 42 Practice) 1. If a∎b = ab − a + b, which of the following has the smallest value? 2. If a⊥b=(a+b)+(a-b), then what is the value of 11⊥9? 3. If a@b means , then what will 4@(5@7) = ? 4. If a@b=(a × b) − (a + b), how much larger is 13@9 than 3@7? 5. If Δ represents the last digit of the corresponding numbers in the following equation: + = 1, what is the digit Δ? |