Question

Erin and her friends are taking a road trip. She has agreed to drive between hours 3 and 6 of the trip. If h represents the hours of the trip Erin will be driving, then h ≥ 3 and h≤ 6 represents her portion of the driving. While she is driving, her distance and time are modeled by the inequality d < 70h. What are the possible hours and distances Erin could be driving?

Answer 1

Solution:

As given

h =Hours of  the trip Erin will be driving.

Also ,   3 ≤ h ≤ 6

d = Distance traveled

The relation between hours of drive and distance traveled is given by inequality

→d < 70 h

→ h > $\frac{d}{70}$

→ As 3 ≤ h ≤ 6

→3 ≤  $\frac{d}{70}$   ≤ 6

→3 × 70 ≤ d ≤ 70 × 6

→ 210 ≤ d ≤ 420

So, h ∈ [3,6] then d ∈ (210,420)

Answer 2

1: to the right 
2:to the left
3:below
4:4.5,200