A company sells two types of notebooks: type A and type B. Type A notebooks cost $3 each, and type B notebooks cost $5 each. If a customer buys 4 type A notebooks and 6 type B notebooks, what is the total cost? Then, if another customer buys 5 type A notebooks and 3 type B notebooks, how much more did the first customer spend compared to the second customer? Let's think step by step and output the final answer within \boxed{}.
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