Question

I need help with 17, 19, 21, and 23.

Answer 1

17. 2x<16 x=7 or lower
All I can help you with is #17,
sorry that I can't answer the other 3.
I hope this helped! :-)

Answer 2

17) Let, the number = x
  It would be: 2x ≥ 16
  Divide both sides by 2, 
  2x/2 ≥ 16
   x ≥ 8

19) Let, the number = x
  5 < x/3 - 11 < 10
 Add 11 to each side, 
 16 < x/3 < 21
Multiply 3 to the each side, 
 48 < x < 63

21) It would be: 1/0.06 < x< 1/0.02
 [ 1 m = 100 cm] so, [6cm = 0.06 m & 2m = 0.02 cm]
 17 < x < 50

23) Let, that number of books = x
It would be: 30 + 1.5x = 60
Subtract 30 from both sides,
1.5x = 30
Divide by 1.5,
x = 20
[Final Answers are in bold letters ]

Hope this helps!