Hey there! 
Guide: 
• The word “sum” means “add” or “addition”
• The word “difference” means “subtract” or “subtraction” 
• The word “product” means “multiply” or “multiplication” 
• The word “quotient” means “divide” or “division” 
NOW THAT WE HAVE ALL OF THAT INFORMATION, WE CAN SOLVE FOR YOUR EQUATION 
“The SUM of a number and 11” 
Well since the “number” is unknown we can label it as “a” so we can know what we’re ADDing to 11…
So, your equation should be: a + 11
Answer: a + 11
Good luck on your assignment and enjoy your day!
~Amphitrite1040:)