15. Doug Upp can shovel coal at the rate of 16 tons per day. His brother, Sid, can e rate of 16 tons per day. His brother, Sid, can shovel 10 tons per day.

a) Define a variable for the number of days Doug has shoveled. Then write an expres

umber of days Doug has shoveled. Then write an expression for the number of

tons Doug has shoveled. X=# days

b)

Three days later, Sid joins Doug, and both shovel together. Write an expression for the num

days Sid has been shoveling in terms of your variable in part a. Then write an expression for the

number of tons Sid has shoveled.

C) Write an equation stating that the total number of tons Doug and Sid have shoveled is 100. Then

solve the equation to find out how many days Doug dug when they have shoveled this much coal.