Pamela Leutwyler

A B

Town A is exactly 100 miles from Town B

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

Let’s replay the motion from the beginning

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

train A

train B

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20

60

train A

train B

fill in the information that isexplicitly stated

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20 x

60

train A

train B

Let x represent the number of hours that train A travels

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20 x

60 x - 1

train A

train B

Let x represent the number of hours that train A travels

train B starts 1 hour later than train Aif A travels for x hours then B travels for x - 1 hours

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20 x

60 x - 1

train A

train B

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20 x

60 x - 1

train A

train B

formula: distance = (rate) x (time)

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20x 20 x

60(x – 1) 60 x - 1

train A

train B

formula: distance = (rate) x (time)

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20x 20 x

60(x – 1) 60 x - 1

train A

train B

distance traveled by train A distance traveled by train B

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20x 20 x

60(x – 1) 60 x - 1

train A

train B

distance traveled by train A distance traveled by train B+ = 100

A B

Town A is exactly 100 miles from Town B

At noon train A leaves town A and travels toward town B at a rate of 20 mph

At 1PM train B leaves town B and travels toward town A at a rate of 60 mph

At what time do the trains meet?

distance rate time (# units of time)

20x 20 x

60(x – 1) 60 x - 1

train A

train B

distance traveled by train A distance traveled by train B+ = 10020x 60(x – 1 )

A B

Town A is exactly 100 miles from Town B

At what time do the trains meet?

distance rate time (# units of time)

20x 20 x

60(x – 1) 60 x - 1

train A

train B

distance traveled by train A distance traveled by train B+ = 10020x 60(x – 1 )

20x + 60 ( x - 1 ) = 10020x + 60x - 60 = 100 80x = 160 x = 2

train A starts at noon and travels for 2 hours before meeting train B

2 PM