Gavyn was thinking of a number. Gavyn divides by 3, then adds 5 to get an answer of 2. What was the original number?

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?

How do you solve a question like this?

Look at this pattern ; 1,4,9, number 10000 belongs in this pattern . what’s the place of this number?