Here is part of a travel graph of Sian's journey from her house to shops and back
69
70
a) What is the speed of Sian from 30 minutes to 45 minutes?
b) What is the distance travelled by Sian in 15 minutes?
c) Find out her average speed and express in km/h.
Answers
Answer:
0 km/Hr
10 km
80/3 km/Hr
Explanation:
Here is part of a travel graph of Sian's journey from her house to shops and back
Graph is not representing Back journey
a) What is the speed of Sian from 30 minutes to 45 minutes?
Distance at 30 min = 20 km
Distane at 45 min = 20 km
Distance from 30 to 45 min = 20 - 20 = 0 km
Time = 45 - 30 = 15 min = 1/4 hr
Speed = 0/(1/4) = 0 km/Hr
b) What is the distance travelled by Sian in 15 minutes?
Let say first 15 min
Distance at 0 min = 0 km
Distance at 15 min = 10 km
Distnace Travelled in 15 min = 10 - 0 = 10 km
Time = 15 min = (1/4) hr
Speed = (10 - 0)/(1/4) = 40 km/Hr
c) Find out her average speed and express in km/h.
Distance Tavelled = 20 km
Time = 45 mins = (3/4) hrs
Average Speed = 20/(3/4) = 80/3 Km/Hr
40 km/h
Explanation:
》• 30 min = 0.5 hour
》• Distance = 20 km
》• V = d/t = 20 km/0.5 h
》• V = 40 km/h