Math answers for the curious

[dragonflymaria]

1. 11/15
2. 1/4
3. 6/5 or 1 1/5
4. a. 8.75 x 10 exp-4
  b. -5.79 x 10 exp2
5. a.  15 600
   b. -0.000781
6. D= BC/A
7. r = (A-P)/Pt
8. x = 8.0 cm
9. x = 60
  Z= 17 cm
10. x = 24