Let’s solve each problem step by step. We’ll use the triangle at the top:
Distance = Speed × Time
Speed = Distance ÷ Time
Time = Distance ÷ Speed
We’ll go section by section.
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Section 1: Calculate the distance travelled
#### a. 3 hours at 40 mph
Distance = Speed × Time = 40 × 3 =
120 miles
#### b. 55 km/h for 3.5 hours
Distance = 55 × 3.5
Let’s calculate:
55 × 3 = 165
55 × 0.5 = 27.5
Total = 165 + 27.5 =
192.5 km
#### c. 4 seconds at 3 m/s
Distance = 3 × 4 =
12 meters
#### d. 5.25 hours at 50 km/h
Distance = 50 × 5.25
50 × 5 = 250
50 × 0.25 = 12.5
Total = 250 + 12.5 =
262.5 km
#### e. 30 mph for 20 minutes
First, convert minutes to hours:
20 minutes = 20/60 = 1/3 hour ≈ 0.333... hours
Distance = 30 × (1/3) =
10 miles
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Section 2: Calculate the average speed
#### a. 150 miles in 5 hours
Speed = Distance ÷ Time = 150 ÷ 5 =
30 mph
#### b. 120 km in 3 hours
Speed = 120 ÷ 3 =
40 km/h
#### c. 20 m in 4 seconds
Speed = 20 ÷ 4 =
5 m/s
#### d. 87.5 miles in 3.5 hours
Speed = 87.5 ÷ 3.5
Let’s divide:
87.5 ÷ 3.5 = ?
Multiply numerator and denominator by 10 to make it easier:
875 ÷ 35 = 25
So,
25 mph
#### e. 9 km in 45 minutes
First, convert minutes to hours:
45 minutes = 45/60 = 0.75 hours
Speed = 9 ÷ 0.75
9 ÷ 0.75 = 9 ÷ (3/4) = 9 × (4/3) = 36/3 =
12 km/h
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Final Answer:
Section 1:
a. Distance = 120 miles
b. Distance = 192.5 km
c. Distance = 12 m
d. Distance = 262.5 km
e. Distance = 10 miles
Section 2:
a. Speed = 30 mph
b. Speed = 40 km/h
c. Speed = 5 m/s
d. Speed = 25 mph
e. Speed = 12 km/h
Parent Tip: Review the logic above to help your child master the concept of distance rate time worksheet.
