Can you please take a look at these 3 problems?
1. A carpentry shop makes dinner tables and coffee tables. Each week the shop must complete at least 9 dinner tables and 13 coffee tables to be shippeed to furniture stores. The shop can produce at most 30 dinner tables and coffee tables combined each week. If the shop sells dinner tables for $120 and coffee tables for $150, how many of each item should be produced for a maximum weekly income? What is the maximum weekly income?

Shop has to produced 30 furnitures.
It must be at least 9 dinner tables for 120$ and 13 coffe tables for 150$.
We noticed that income will be greater when shop will produce as much is possible coffe tables.
So if sum of furnitures is 30, shop should produce 9 (minimum) of dinner tables and the rest of cofee tables.
There are 9 dinner tables and 30-9=21 coffe tables.
Income is equal:
120*9+21*150=4230$

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