Which of the following of decreased by 15% every time X increase by one

Leo is going to use a random number generator 4 0 0 400 times. each time he uses it, he will get a 1 , 2 , 3 , 4 , 1,2,3,4, or 5 5. what is the best prediction for the number of times that leo will get an odd number?

Write two subtraction equations that are equivalent to 5 + 12 = 17.

Just tell me how to set up the equation.