Distance Speed and Time Calculating Speed Hrs and Min Calculating Distance Speed Distance or Time : Which Operation Hrs and Min Calculating Time Hrs and.

Distance Speed and Time

Calculating Speed

Hrs and Min

Calculating Distance

Speed Distance or Time : Which Operation

Hrs and Min

Calculating Time Hrs and Min

Hrs and Min : Intro

Speed Distance Time

Distance = Speed x Time

S = D ÷ T

Speed = Distance ÷ Time

D = S x T

T = D ÷ S

Time = Distance ÷ Speed

D

S T

Units

DST … Distance

D

S TX

To find Distance formula Cover D in DST triangle

T

=

S

D

Distance = Speed x Time

D = S x T

Examples

DST …. Speed

D

S TS = D ÷ T

Speed = Distance ÷ Time

÷

To find Speed formula Cover S in DST triangle

S =

D

T

= D T

Examples

DST ….. Time

D

S TT = D ÷ S

÷

To find Time formula Cover T in DST triangle

DT = D T

S

=

Time = Distance ÷ Speed

Examples

Units

S

D

T

Speed is the “key” when checking units

A speed of 60 mph is

60 miles

1 hour

60 mph

60 milesin 1 hour

Distance must be in miles

Time in hours

Units

S

D

T

Speed is the “key” when checking units

A speed of 12m/s is

12 m

1 sec12 m/s

12 metre

in 1 second

Distance must be in metres

Time in seconds

Units

S

D

T

60 km

1 hr60 km/hr

60 km

in 1 hour

Speed is km

/ hr

Units

S

D

T

25 cm

1 sec25 cm/s

25 cm

in 1 sec

Speed is cm

/ sec

60What’s the speed limit?

At this speed, how far would

you travel

in 1 hour?

60 miles per hour

60

1 2 3 4 hrs

0

120

60

180

60

Same distance for next hour

60

After 2 hrs ….. 60 x 2 = 120

After 3 hrs….. 60 x 3 = 180

45 1 hour?

miles per hour

45

1 2 3 4 hrs

0

90 135

45 x 1 = 45

45

2 hour? 45 x 2 = 90

3 hour? 45 x 3 = 135

4 hour? 45 x 4 = 180

180

Start Next

Rule for Distance

To find the distance travelled at a speed of S you multiply by the time taken for the journey

Distance

Speed Time= x

D S T= x

The next slide shows how to get this FORMULA from a DST triangle

Distance =

120

6D

Tx TS

Time = 6 hourSpeed = 120 km/hr

Find rule for Distance

720 km

D

S

=

x

D =

x

6120D =

Distance=

D

S TX TS

Time = 3 hr

D = S x T

60 X 3Speed= 60mph

Find Distance

D = S x T

D =

D = 180 miles

What can you find

1215

D

S X T

Time = sec

D = S x T

X

Speed= m/s

180 miles

15 12

D ==

Can find distance

Finding Distance

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

x

T

D

S

T=

S=

100 km/hr

hr

Distance

D = S x T

x

S = D ÷ T

T = D ÷ S

D= km

÷÷

Clear

minT= 4 h

r

hr

min

Parts of an Hour

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

New Speed

Clear

¼ ½ ¾

0.25

1

60

1

min

dec

5

8= 5 ÷ 8 = 0.625

9 18 27 360 Distance Travelled

D = 36 x 0.75 = 27

hour

Speed = 36 mph

D = S x T

Parts of an Hour

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

New Example

Clear

15

30 45

0.25

0.5 0.75 1

60 min

dec

Speed = 32 mph

D = S x T =

2 hrs

¼ ½ ¾ 1 hour

30 min

= 2.5 hrs

=

3 hrs 15 min = 3 +0.25 hrs = 3.25 hrsExample

Finding Distance – Hrs and Min

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

x

T

D

S

T=

S=

32 km/hr

3 hr

Distance

D = S x T

x

S = D ÷ T

T = D ÷ S

D= km

÷÷

Clear

15 minT= h

r

hr

min

Finding Speed

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

New Example

Clear

A train took hours to travel a distance of miles. If the train was travelling at the same rate then the speed in miles per hour is

4

hour

= 180

hour

= 180 ÷ 4 = 45

opposite of x is ÷ Each hour the train travels miles.

Speed

= Distance ÷ Time

SD

T=

4 180

x

45

Speed = 45 miles per hour

Finding Speed

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

x

T

D

S

T=

S=

km/hr

hr

D = S x T

x

S = D ÷ T

T = D ÷ S

D= 400 km

÷÷

Clear

minT= 4 h

r

hr

min

New Example

Finding Speed … Hrs & Min

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

x

T

D

S

T=

S=

km/hr

1 hr

D = S x T

x

S = D ÷ T

T = D ÷ S

D= 96 km

÷÷

Clear

30 minT= h

r

hr

min

New Example

Finding Time

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

x

T

D

S

T=

S=

20 km/hr

hr

Find Time

D = S x T

x

S = D ÷ T

T = D ÷ S

D= 80 km

÷÷

Clear

minT= h

r

hr

min

Finding Time Hrs Min

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

x

T

D

S

T=

S=

36 km/hr

hr

Find Time

D = S x T

x

S = D ÷ T

T = D ÷ S

D= 198 km

÷÷

Clear

minT= h

r

hr

min

Finding Speed , Distance or Time

0 1 2 3 4

5 6 7 8 91÷4

C

.

÷x

0.25+ On

²

-

Ans

=

√(-)

x

T

D

S

40

80

T=S=

40 km/hr

hr

D or S or T

x

T = D ÷ S

T = 80 ÷ 40

T= 2

D= 80 km

÷÷

Clear

minT= h

r

hr

min

D S T Hrs

D S T Hrs Min

Parts of an Hour

0 1 2 3 4

5 6 7 8 9

C

.

÷x

0+ On

²

-

Ans

=

√(-)

New Example

Clear

1

0.5

0.250.75

30

45 15