Worksheet titled "Speed, Distance and Time Worksheet 1" featuring a triangle diagram and problems for calculating distance and average speed.

Here are the step-by-step solutions for the worksheet.

Section 1: Calculate the distance

*Formula: Distance = Speed × Time*

a. 3 hours at 40 mph
* Calculation: $40 \times 3 = 120$
* Distance = 120 miles

b. 55 km/h for 3.5 hours
* Calculation: $55 \times 3.5 = 192.5$
* Distance = 192.5 km

c. 4 seconds at 3 m/s
* Calculation: $3 \times 4 = 12$
* Distance = 12 m

d. 5.25 hours at 50 km/h
* Calculation: $50 \times 5.25 = 262.5$
* Distance = 262.5 km

e. 30 mph for 20 minutes
* *Note: The speed is in hours, but time is in minutes. We must convert minutes to hours first.*
* Conversion: 20 minutes is $\frac{20}{60}$ of an hour, which simplifies to $\frac{1}{3}$ hour.
* Calculation: $30 \times \frac{1}{3} = 10$
* Distance = 10 miles

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Section 2: Calculate the average speed

*Formula: Speed = Distance ÷ Time*

a. 150 miles in 5 hours
* Calculation: $150 \div 5 = 30$
* Speed = 30 mph

b. 120 km in 3 hours
* Calculation: $120 \div 3 = 40$
* Speed = 40 km/h

c. 20 m in 4 seconds
* Calculation: $20 \div 4 = 5$
* Speed = 5 m/s

d. 87.5 miles in 3.5 hours
* Calculation: $87.5 \div 3.5 = 25$
* Speed = 25 mph

e. 9 km in 45 minutes
* *Note: The answer asks for km/h, so we need to convert the time (45 minutes) into hours.*
* Conversion: 45 minutes is $\frac{45}{60}$ hours. This simplifies to $\frac{3}{4}$ or $0.75$ hours.
* Calculation: $9 \div 0.75 = 12$
* Speed = 12 km/h

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Final Answer:

Section 1
a. 120 miles
b. 192.5 km
c. 12 m
d. 262.5 km
e. 10 miles

Section 2
a. 30 mph
b. 40 km/h
c. 5 m/s
d. 25 mph
e. 12 km/h