Answer:
$360
Step-by-step explanation:He started with $150 and he kept adding 30 every month (value of x would be number of months). The months between January and July are 7 so that's your value for x. The equation set up would be 150+30x= ?. The question is asking to solve for x. We know the value of x is 7 so your next equation would look like this: 150+30(7)= ?. Then you enter the equation into the calculator and you should get 360.