5
QuizMultiple Choice
Writing Equations
Question 5 • Common Core Math 7 B-IC
Javier asks his mother how old a tree in their yard is. His mother says, “The sum of 10 and two-thirds of that tree’s age, in years, is equal to 50.” Javier writes the equation , where a is the tree’s age in years. His equation is not correct. What error did he make?
Answer
A
The variable a should be multiplied by 10 only, and then added to .
B
The variable a should be multiplied by only and then added to 10.
C
The variable a should be multiplied by 50, not by the sum of 10 and .
D
The variable a should be multiplied by and 50 and set equal to 10.