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km to miles London 5 miles (8 km) To convert between miles and kilometres and vice versa it is useful to remember the fact that 5 miles  8 km. Although this is an approximation it happens to be a very good one with an error of less than 1%. 8 km 5 miles So if 8 km  5 miles 1 km  5 8 Mile (  both sides by 8) 1 km { 5 8 mile { Metric/Imperial Measures (Distance).

Paris 16 km Berlin 24 km To make very rough, quick mental calculations between km and miles you could use 1 km  ½ mile but you should be aware that your answers will be much less accurate (by about 20%). If you decide to use this method you could improve it by “adding something on” to your answer, (ideally 25%). Find the distances in miles. 16 x 5 8 = 10 miles (accurate) 16 x 1 2 = 8 miles (very rough) 24 x 5 8 = 15 miles (accurate) 24 x 1 2 = 12 miles (very rough) Metric/Imperial Measures (Distance). 1 km = 5 8 mile

Pisa 50 km Milan 80 km To make very rough, quick mental calculations between km and miles you could use 1 km  ½ mile but you should be aware that your answers will be much less accurate (by about 20%). If you decide to use this method you could improve by “adding something on” to your answer, (ideally 25%). Find the distances in miles. 50 x 5 8 = miles (accurate) 50 x 1 2 = 25 miles (very rough) 80 x 5 8 = 50 miles (accurate) 80 x 1 2 = 40 miles (very rough) Metric/Imperial Measures (Distance). 1 km = 5 8 mile

Prague 96 km Rome 150 km To make very rough, quick mental calculations between km and miles you could use 1 km  ½ mile but you should be aware that your answers will be much less accurate (by about 20%). If you decide to use this method you could improve by “adding something on” to your answer, (ideally 25%). Find the distances in miles. 96 x 5 8 = 60 miles (accurate) 96 x 1 2 = 48 miles (very rough) 150 x 5 8 = miles (accurate) 150 x 1 2 = 75 miles (very rough) Metric/Imperial Measures (Distance). 1 km = 5 8 mile

Questionkmmiles (accurate) miles (very rough) Complete the table below. Metric/Imperial Measures (Distance).

Questionkmmiles (accurate) miles (very rough) 142½2 263¾ ½ ½150 Complete the table below. Metric/Imperial Measures (Distance).

miles to km London 5 miles (8 km) To convert between miles and kilometres and vice versa it is useful to remember the fact that 5 miles  8 km. Although this is an approximation it happens to be a very good one with an error of less than 1%. 8 km 5 miles If 5 miles  8 km 1 mile  8 5 km (  both sides by 5) 1 mile { 1 mile  1.6 km 1.6 km { Metric/Imperial Measures (Distance).

To make rapid mental calculations when converting miles to km you might want to consider the following two methods. Method 1 is about 20% too big and method 2 is about 6% too small. You could obviously improve on these rough estimates by making appropriate corrections. 1 mile = 1.6 km Mental method 1 (very rough ) 66 miles x km Mental method 2 ( rough ) Add on ½ again 99 km Accurate Calculation 66 x 1.6 = km Consider the following example of converting 66 miles into km. ( ) Metric/Imperial Measures (Distance).

1 mile = 1.6 km Mental method 1 (very rough ) 120 miles x km Mental method 2 ( rough ) Add on ½ again 180 km Accurate Calculation 120 x 1.6 = 192 km Consider the following example of converting 120 miles into km. ( ) Which method do you think works best? Metric/Imperial Measures (Distance). To make rapid mental calculations when converting miles to km you might want to consider the following two methods. Method 1 is about 20% too big and method 2 is about 6% too small. You could obviously improve on these rough estimates by making appropriate corrections.

Metric Imperial measures (distance). Paris 10 miles Berlin 18 miles Find the distances in km. 10 x 1.6 = 16 km = 15 km (rough) 10 x 2 = 20 km (very rough) 1 mile = 1.6 km 18 x 1.6 = 28.8 km = 27 km (rough) 18 x 2 = 36 km (very rough) To make rapid mental calculations when converting miles to km you might want to consider the following two methods. Method 1 is about 20% too big and method 2 is about 6% too small. You could obviously improve on these rough estimates by making appropriate corrections.

Pisa 40 miles Milan 56 miles 40 x 1.6 = 64 km = 60 km (rough) 40 x 2 = 80 km (very rough) 1 mile = 1.6 km 56 x 1.6 = 89.6 km = 84 km (rough) 56 x 2 = 112 km (very rough) Find the distances in km. Metric/Imperial Measures (Distance). To make rapid mental calculations when converting miles to km you might want to consider the following two methods. Method 1 is about 20% too big and method 2 is about 6% too small. You could obviously improve on these rough estimates by making appropriate corrections.

Prague 116 miles Rome 200 miles 116 x 1.6 = km = 174 km (rough) 116 x 2 = 232 km (very rough) 1 mile = 1.6 km 200 x 1.6 = 320 km = 300 km (rough) 200 x 2 = 400 km (very rough) Find the distances in km. Metric/Imperial Measures (Distance). To make rapid mental calculations when converting miles to km you might want to consider the following two methods. Method 1 is about 20% too big and method 2 is about 6% too small. You could obviously improve on these rough estimates by making appropriate corrections.

Questionmiles km (accurate) km (rough + ½) km (very rough x 2) Complete the table below. Metric/Imperial Measures (Distance).

Questionmiles km (accurate) km (rough + ½) km (very rough x 2) 1587½ Complete the table below. Metric/Imperial Measures (Distance).

yards to m cm Metre = 100 cm 1 ft 2 ft 3 ft ft/inches 1 Yard  90 cm 1 Yard = 3 feet = 36 inches A yard is SMALLER than a metre. Metric/Imperial Measures (Distance). To convert between yards and metres and vice versa it is useful to remember the fact that 1 yd  0.9 m. This is a good approximation with an error of about 1%.

22 yards Find the length of the cricket pitch in metres. 22 x 0.9 = 19.8 m To convert between yards and metres and vice versa it is useful to remember the fact that 1 yd  0.9 m. This is a good approximation with an error of about 1%.

Metric/Imperial Measures (Distance). Find the length and width of the basket ball court in metres (nearest cm). Length = 28 x 0.9 = 25.2 m 28 yards 16.5 yards Width = 16.5 x 0.9 = m To convert between yards and metres and vice versa it is useful to remember the fact that 1 yd  0.9 m. This is a good approximation with an error of about 1%.

Metric/Imperial Measures (Distance). Find the length and width of the piece of wood in metres (nearest cm). Length = 2.9 x 0.9 = 2.61 m Width = 0.74 x 0.9 = 0.67 m 0.74 yards 2.9 yards To convert between yards and metres and vice versa it is useful to remember the fact that 1 yd  0.9 m. This is a good approximation with an error of about 1%.

Questionyards metres Complete the table below. Metric/Imperial Measures (Distance).

Questionyards metres Complete the table below. Metric/Imperial Measures (Distance).

m to yards cm yard  0.9 m 1 ft 2 ft 3 ft ft/inches Metric/Imperial Measures (Distance). If 0.9 m  1 yd 1 m  1.1 yds m  yds (  both sides by 0.9) 1 Yard m  1.1 yds This is also a good approximation with an error of about 1%.

Metric/Imperial Measures (Distance). 1 m  1.1 yds This is also a good approximation with an error of about 1%. Find the height and width of the door in yards. 2 m 1.3 m height = 2 x 1.1 = 2.2 yds width = 1.3 x 1.1 = 1.43 yds

Metric/Imperial Measures (Distance). 1 m  1.1 yds This is also a good approximation with an error of about 1%. Find the length and width of the playing pitch in yards. length = 105 x 1.1 = yds width = 40 x 1.1 = 44 yds 105 m 40 m

Metric/Imperial Measures (Distance). 1 m  1.1 yds This is also a good approximation with an error of about 1%. Find the height of the Eiffel Tower in yards. 320 m height = 320 x 1.1 = 352 yds

Questionmetres yards Complete the table below. Metric/Imperial Measures (Distance).

Questionmetres yards Complete the table below. Metric/Imperial Measures (Distance).

inches to cm cm Metre = 100 cm 1 ft 2 ft 3 ft ft/inches 1 Yard  90 cm 1 Yard = 3 feet = 36inches Metric/Imperial Measures (Distance). If 36 inches  90 cm inch  cm (  both sides by 36) 1 inch  2.5 cm 1 inch  2.5 cm This is a good approximation with an error of about 1%.

Metric/Imperial Measures (Distance). 1 inch  2.5 cm This is a good approximation with an error of about 1%. Find the length of both strips of wood in cm. A = 8 x 2.5 = 20 cm B = 11 x 2.5 = 27.5 cm A B 1 ft inches

Metric/Imperial Measures (Distance). 3.4 inches 2.2 inches 1 inch  2.5 cm This is a good approximation with an error of about 1%. Find the dimensions of the playing card in cm. length = 3.4 x 2.5 = 8.5 cm width = 2.2 x 2.5 = 5.5 cm

Metric/Imperial Measures (Distance). 1 inch  2.5 cm This is a good approximation with an error of about 1%. Find the dimensions of the pool table in cm. length = 84 x 2.5 = 210 cm width = 36 x 2.5 = 90 cm 84 inches 36 inches

Questioninches cm Complete the table below. Metric/Imperial Measures (Distance).

Questioninches cm Complete the table below. Metric/Imperial Measures (Distance).

cm to inches cm Metre = 100 cm 1 ft 2 ft 3 ft ft/inches 1 Yard  90 cm 1 Yard = 3 feet = 36inches Metric/Imperial Measures (Distance). If 2.5 cm  1 inch cm  inches (  both sides by 2.5) 1 cm  0.4 inches 1 cm  0.4 inches This is a good approximation with an error of about 1%.

Metric/Imperial Measures (Distance). Find the length of both strips of wood in inches. A = 15 x 0.4 = 6 inches B = 24 x 0.4 = 9.6 inches 1 cm  0.4 inches This is a good approximation with an error of about 1% cm A B

Metric/Imperial Measures (Distance). 9 cm 6.5 cm Find the dimensions of the playing card in inches. length = 9 x 0.4 = 3.6 inches width = 6.5 x 0.4 = 2.6 inches 1 cm  0.4 inches This is a good approximation with an error of about 1%.

Metric/Imperial Measures (Distance). Find the dimensions of the pool table in inches. length = 200 x 0.4 = 80 inches width = 34 x 0.4 = 13.6 inches 1 cm  0.4 inches This is a good approximation with an error of about 1%. 200 cm 34 cm

Questioncm inches Complete the table below. Metric/Imperial Measures (Distance).

Questioncm inches ½ Complete the table below. Metric/Imperial Measures (Distance).

Worksheets Questionkmmiles (accurate)miles (very rough) Complete the table below. Worksheet 1

Questionmiles km (accurate)km (rough + ½)km (very rough x 2) Complete the table below. Worksheet 2

Questionyards metres Complete the table below. Worksheet 3

Questionmetres yards Complete the table below. Worksheet 4

Questioninches cm Complete the table below. Worksheet 5

Questioncm inches Complete the table below. Worksheet 6