1. Which is greater than 4? (a) 5, (b) -5, (c) -1/2, (d) -25.
2 answers:
You might be interested in
Let's write some equations.
Mingwei's distance from Town A after
hours from 8:00 is 
.
Ali's distance from Town B after hours is 
, since he doesn't start walking for 40 minutes.
When Mingwei's distance is twice Ali's, they've met up (since their distance from Town A is twice their distance from Town B).
So, this gives
, so 
, so 
, so the time is 10:40.
After
hours, Mingwei has traveled 
kilometers while Ali has traveled sixty, so the distance between the towns is 
kilometers.
Mingwei's distance from Town A after
Ali's distance from Town B after
When Mingwei's distance is twice Ali's, they've met up (since their distance from Town A is twice their distance from Town B).
So, this gives
After