Word problem: (I only need the answer and explanation no need statements PLS HELP )
The weight of Jack is 30kg 500g. The weight of Dereck is 28kg 700g. What is their total weight? Also, find the difference of their weight?

Solve 2x+y=3 x+y=5 in substitution method

Four individuals pool money together to start a new business and agree to split the profits equally. n invests $6,000, x invests $2,000, y invests $8,000 and z invests $4,000. if the profits for the first month were $100,000, y receives than if the profits were divided in proportion to how much they invested.

Aparking garage charges $1.12 for the first hour and 0.50 for each additional hour. what is the maximum length of time tom can park in the garage if we wishes to play no more than $5.62