1. Add fractions using a common denominator. Here, that would be 10.
.. 3/5 -1/2 -(-1)
.. = 6/10 -5/10 +1
.. = 1/10 +1
.. = 1 1/10 . . . . . . . [tex]1 \frac{1}{10}[/tex]
2. The coordinate of the left point would normally be subtracted from that of the right point to find the distance between them: -6 -(-9) = -6 +9 = 3.
.. A. -9 +(-6) = -15 . . . . wrong
.. B. |-9| -|-6| = 9 -6 = 3 . . . . right distance; inappropriate calculation method
.. C. 6 - 9 = -3 . . . . . . maybe right. We usually consider distance to be positive.
.. D. |-6| -(-9) = 6 +9 = 15 . . . . wrong
3. Using your memory, long division, or your calculator, you find -3/4 = -0.75
4. (1/2)(-7 +21 -(-3 1/2))
.. = (1/2)(14 +3 1/2)
.. = (1/2)(17 1/2)
.. = (1/2)(17) +(1/2)(1/2)
.. = (8 1/2) +1/4
.. = (8 2/4) +1/4
.. = 8 3/4
_____
For problem 2, I would choose "none of the above" and complain to the teacher that the question has no appropriate answer. (Yet another example of math curriculum material that is more misleading than instructive.)
