At 7 a.m., Ahmad started from City F and travelled towards City G and his speed remained constant throughout. At 10 a.m., Mary started her journey from City F towards City G at an average speed of 90 km/h. Mary overtook Ahmad at 1 p.m. After overtaking, Mary carried on her journey at the same average speed and reached at City G at 3:50 p.m.
- Find Ahmad's average speed in km/h.
- What is the distance between the two cities?
(a)
From 10 a.m. to 1 p.m. = 3 h
Distance that Mary had travelled until Mary overtook Ahmad
= 3 x 90
= 270 km
From 7 a.m. to 1 p.m. = 6 h
Ahmad's average speed
= 270 ÷ 6
= 45 km/h
(b)
From 10 a.m. to 3:50 p.m. = 5 h 50 min
1 h = 60 min
5 h 50 min = 5
50 60
h = 5
56 h
Distance between the two cities
= 5
56 x 90
=
356 x 90
= 525 km
Answer(s): (a) 45 km/h; (b) 525 km