Wei has $150.00 to make a garland using 60-cent balloons. He wants to purchase 100 blue balloons and some number of white balloons. He learns that the white balloons are on sale for half price. He writes and solves an equation to find the number of white balloons he can purchase. Which models can be used to solve the problem?

100 b plus w equals 150; 100 b plus w equals 150
100 b plus w equals 150; 100 b plus 30 equals 150
0.60 b plus 0.30 w equals 150; 60 plus 0.30 w equals 150
0.60 b plus 0.30 w equals 150; 100 plus 0.30 w equals 150