Read this word problem
On a cold February morning, Coltan checked the temperature on his phone and saw that it was -3 C. When he checked again after school, the temperature had dropped 3 C. What was the temperature after school?
To solve the problem, Ellen subtracted -3-(-3) and came up with an answer of 0 C is Ellen correct? Why or why not?
1 answer
Ellen is not correct. When subtracting a negative number from another negative number, it is similar to adding a positive number. In this case, -3-(-3) is the same as -3+3, which equals 0. Since the temperature dropped by 3 degrees after school, the correct calculation should be -3-3, which equals -6. Therefore, the temperature after school was -6°C.