Mathematics Unit 12: Length

Mathematics Unit 12: Length

Mr Vinc Chin

Millimetres and Centimetres

• mm to cm  $\div10$  

• cm to mm  $\times10$  

4.9 cm

= 4.9 x 10

= 49 mm

 $\frac{1}{5}​cm=0.2cm$  
​= 0.2 cm x 10
= 2 mm

72 mm
= 72 $\div$  10

= 7.2 cm 

Centimetres to Metres

• cm to m  $\div100$  

• m to cm  $\times100$  

38 cm
 $=38\div100$  

= 0.38 m

 $1\frac{1}{2}$  m = 1.5 m
= 1.5 x 100
= 150 cm

260 cm
 $=260\div100$  

= 2.6 m 

Metres and Kilometres

• m to km $\div1000$  

• km to m $\times1000$  

6km 50m = ______km

6km 50m =

= 6 km + 0.05 km

= 6.05 km

 $1\frac{3}{4}$  km = ____ m

 $1\frac{3}{4}$  km = 1.75 km
= 1.75 x 1000
= 1750 m

 0.8 km = ______m

 0.8 km = 0.8 x 1000

= 800 m

Addition of Length

95 cm + 5.07 m = _____cm

95 cm + 5.07 m

= 95 cm + 507 cm

= 602 cm

 $\frac{4}{5}$  km + 92 m + 6.03km = _____m

= 0.8 km + 92 m + 6.03km 
= 800 m + 92 m + 6030 m
= 6922 m

12 cm + 54 mm +  $\frac{7}{10}$   cm = _____mm

= 12 cm + 54 mm + 0.7 cm
= 120 mm + 54 mm + 7 mm
= 181 mm

Subtraction of Length

 $7\frac{1}{5}m-0.79m=_{ }$  

= 7.2 m  - 0.79 m
= 6.41 m

 $\frac{3}{4}$ m  - 26 cm - 0.15 m = _____cm

= 0.75 m - 26 cm - 0.15 m

= 75 cm - 26 cm - 15 cm
= 34 cm

 $1\frac{3}{10}$  km - 0.029 km - 698 m = ____m

= 1.3 km - 0.029 km - 698 m
= 1300 m - 29 m - 698 m
= 573 m

Multiplication of Length

Division of Length

 $1.26km\ \times2\times7=\ \ \ \ \ m$  

 $1.26km\ \times2\times7=\ \ \ \ \ m$  

17 640m

 $3.05m+3.05m+65cm=\ \ \ \ \ m$  
(Answers convert into fractions)

 $3.05m+3.05m+65cm=\ \ \ \ \ m$  
(Answers convert into fractions)

 $6\frac{3}{4}m$  

 $4.36km-\frac{4}{5}km=\ \ \ \ \ \ km$  

(Answers in decimals)

 $4.36km-\frac{4}{5}km=\ \ \ \ \ \ km$  

(Answers in decimals)

3.56km

 $19m\ 80cm\div4=\ \ \ \ \ \ \ cm$  

 $19m\ 80cm\div4=\ \ \ \ \ \ \ cm$  

495cm