Could someone help me with these 2 questions?!

i will mark brainliest!

Three times the sum of a number and seven is negative thirty-six. what is the number?

Boris needs to buy plastic spoons. brand a has a box 42 spoons for $2.37. brand b has a box of 72 spoons for $3.57. find the unit price for each brand. then state which brand is the better buy based on the unit price. round your answer to the nearest cent.

How long does it take natsumi to clean up after she is done? table: .area time30. 245. 2.7560. 3.5