How much higher is checkpoint 4 than checkpoint 1
checkpoint 1= -86
checkpoint 4= 2,177

Answer is 2263.
Checkpoint 1 is -86 
Checkpoint 4 is 2177
Subtract -86 from 21772177-(-86)
   =2263
2263 is how much higher checkpoint 1 (-86) is from checkpoint 4 (2177)

Hope this helps! :)

2177- -86=2263
turn the subtraction in to add and the negative into positive then add both numbers

The answer is 1 because you have to flip the sign when dividing by negative number and 3

Multiply 9 and 67. then multiply 3 with 67. lastly the answer that you got for 9x67 is to be subtracted by the answer you got for 3x67