Answer:
28. x = 5
29. x = 8
30. No solution.
Step-by-step explanation:
28. Given that 200 < 3x³ < 400
⇒ 66.67 < x³ < 133.33
⇒ 4.07 < x < 5.1
As x is an integer, so, x = 5 (Answer)
29. Given that 350 < 7x² < 450
⇒ 50 < x² < 64.28
⇒ 7.07 < x < 8.01 {As x is a positive integer}
So, x = 8 (Answer)
30. Given that x + 2 < 5717 < x + 3
⇒ x < 5715 and x > 5714
As x is integer, so there is no solution for this problem. (Answer)
