SME
Grade 6 Math · Problem type
Constant speed
Use this for “6 miles in 2 hours. How long for 15 miles?” at the same speed.
Diagram
Time: 2.5 h on the top line sits over 150 km on the bottom line: each 1 above is 60 below.
This is an example. Type your own values to start a new problem.
Speed (km/h)
×
Time (h)
=
Distance (km)
Formulas
60 × 2.5 = 150
Speed × time = distance
Assumptions
•
The speed stays the same the whole way.
•
Speed is the distance in one unit of time: 1 hour for km/h or mph.
•
Times to 100 hours (half an hour is 0.5); distances and speeds in kilometers or miles.
Step-by-step
WE KNOW
Distance: 150 km
Time: 2.5 h
FIND
speed
Step 1 · Find speed
? × 2.5 = 150
Speed × time = distance
Speed is the distance in one unit of time: share the distance equally among the units of time.
150 ÷ 2.5 = 1,500 ÷ 25
6
0
25
)
1
5
0
0
−
1
5
0
0
Speed = 60 km/h
Check
Put the numbers back in. Both sides should match.
60 × 2.5 = 150 ✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.