What is the value of 5a+2(a+b)5a+2(a+b) when a = 4 and b = 2?

What is the simplified expression for 6(2(y+x))

Twenty-five percent of the customers entering a grocery store between 5 p.m. and 7 p.m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

Find the maximum value of p= 4x + 5y subject to the following constraints :