How many different combinations are there of the digits 46987?

Acomputer store bought a program at a cost of $10 and sold it for $13. find the percent markup

For what values of the variable x is the expression square root of 7x+14+ square root of 7-x a real number?

Luke wants to reduce the area of his rectangular garden by 1/4 the expression 14/w can be used to represent this change. what is another way to write this expression?