I need help with this question :p

Giuseppi's pizza had orders for $931.00 of pizzas. the prices were $21 for a large pizza, 514 for a medium pizza, and $7 for a small pizza. the number of large pizzas was two less than four times the number of medium pizzas. thenumber of small pizzas was three more than three times the number of medium pizzas. how many of each size of pizza were ordered?

An ulcer medication has 300 milligrams in 2 tablets. how many milligrams are in 3 tablets?

What’s the answer ? use the picture to see the problem