Exercise 2 Page 330

Let's write an inequality that describes Craig's desired earnings. The phrase at least is equivalent to saying greater than or equal to, which algebraically can be written as $\ge .$ Therefore, we can describe Craig's desired earnings. Next, let's find how much money Craig earns in a week by working $40$ hours. The pay rate is $\$12.80$ per hour so we can find the total weekly earnings multiplying this rate by $40$ hours. Craig can earn $\$512$ in a week by working $40$ hours but this is not enough to reach Craig's earnings goal, so he needs to put in overtime. We know that Craig is paid $\$19.20$ per hour of overtime. So, if the extra number of hours Craig needs to put in to earn at least $\$600$ is $x,$ we can rewrite the left-hand side of our inequality with the expression $19.20x.$ By solving this inequality for $x$ we can determine the number of hours Craig has to put in. We are only given whole hours as options, and since Craig wants to earn at least $\$600$ we have to round up the number of extra hours Craig has to put in to $5$ hours. In total Craig has to put in $45$ hours, which corresponds to option H.