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2. 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).

3. 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

4. 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 = 31.25 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

5. 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 = 93.75 miles (accurate) 150 x 1 2 = 75 miles (very rough) Metric/Imperial Measures (Distance). 1 km = 5 8 mile

6. Questionkmmiles (accurate) miles (very rough) 14 26 38 432 556 660 772 8120 9200 10300 Complete the table below. Metric/Imperial Measures (Distance).

7. Questionkmmiles (accurate) miles (very rough) 142½2 263¾3 3854 4322016 5563528 66037½30 7724536 81207560 9200125100 10300187½150 Complete the table below. Metric/Imperial Measures (Distance).

8. 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).

9. 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 2 132 km Mental method 2 ( rough ) Add on ½ again 99 km Accurate Calculation 66 x 1.6 = 105.6 km Consider the following example of converting 66 miles into km. (66 + 33) Metric/Imperial Measures (Distance).

10. 1 mile = 1.6 km Mental method 1 (very rough ) 120 miles x 2 240 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. (120 + 60) 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.

11. Metric Imperial measures (distance). Paris 10 miles Berlin 18 miles Find the distances in km. 10 x 1.6 = 16 km 10 + 5 = 15 km (rough) 10 x 2 = 20 km (very rough) 1 mile = 1.6 km 18 x 1.6 = 28.8 km 18 + 9 = 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.

12. Pisa 40 miles Milan 56 miles 40 x 1.6 = 64 km 40 + 20 = 60 km (rough) 40 x 2 = 80 km (very rough) 1 mile = 1.6 km 56 x 1.6 = 89.6 km 56 + 28 = 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.

13. Prague 116 miles Rome 200 miles 116 x 1.6 = 185.6 km 116 + 58 = 174 km (rough) 116 x 2 = 232 km (very rough) 1 mile = 1.6 km 200 x 1.6 = 320 km 200 + 100 = 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.

14. Questionmiles km (accurate) km (rough + ½) km (very rough x 2) 15 26 310 432 556 660 772 8120 9200 10300 Complete the table below. Metric/Imperial Measures (Distance).

15. Questionmiles km (accurate) km (rough + ½) km (very rough x 2) 1587½10 269.6912 310161520 43251.24864 55689.684112 6609690120 772115.2108144 8120192180240 9200320300400 10300480450600 Complete the table below. Metric/Imperial Measures (Distance).

16. yards to m 1020 30 40 50 6070 80 90 cm 100 1 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%.

17. 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%.

18. 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 = 14.85 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%.

19. 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%.

20. Questionyards metres 11 23 310 40.5 518 620 750 8100 9250 101500 Complete the table below. Metric/Imperial Measures (Distance).

21. Questionyards metres 110.9 232.7 3109 40.50.45 51816.2 62018 75045 810090 9250225 1015001350 Complete the table below. Metric/Imperial Measures (Distance).

22. m to yards 1020 30 40 50 6070 80 90 cm 100 1 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 1 0.9 1 m  yds (  both sides by 0.9) 1 Yard 1.1 1 m  1.1 yds This is also a good approximation with an error of about 1%.

23. 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

24. 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 = 115.5 yds width = 40 x 1.1 = 44 yds 105 m 40 m

25. 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

26. Questionmetres yards 11 23 310 40.5 518 620 750 8100 9250 101500 Complete the table below. Metric/Imperial Measures (Distance).

27. Questionmetres yards 111.1 233.3 31011 40.50.55 51819.8 62022 75055 8100110 9250275 1015001650 Complete the table below. Metric/Imperial Measures (Distance).

28. inches to cm 1020 30 40 50 6070 80 90 cm 100 1 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 90 36 1 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%.

29. 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 0 6 12

30. 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

31. 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

32. Questioninches cm 11 23 34 40.5 56 612 715 818 920 1024 Complete the table below. Metric/Imperial Measures (Distance).

33. Questioninches cm 112.5 237.5 3410 40.51.25 5615 61230 71537.5 81845 92050 102460 Complete the table below. Metric/Imperial Measures (Distance).

34. cm to inches 1020 30 40 50 6070 80 90 cm 100 1 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 1 2.5 1 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%.

35. 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%. 10 20 30 cm A B

36. 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%.

37. 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

38. Questioncm inches 12.5 25 31.25 46 510 68 715 820 925 1030 Complete the table below. Metric/Imperial Measures (Distance).

39. Questioncm inches 12.51 252 31.25½ 462.4 5104 683.2 7156 8208 92510 3012 Complete the table below. Metric/Imperial Measures (Distance).

40. Worksheets Questionkmmiles (accurate)miles (very rough) 14 26 38 432 556 660 772 8120 9200 10300 Complete the table below. Worksheet 1

41. Questionmiles km (accurate)km (rough + ½)km (very rough x 2) 15 26 310 432 556 660 772 8120 9200 10300 Complete the table below. Worksheet 2

42. Questionyards metres 11 23 310 40.5 518 620 750 8100 9250 101500 Complete the table below. Worksheet 3

43. Questionmetres yards 11 23 310 40.5 518 620 750 8100 9250 101500 Complete the table below. Worksheet 4

44. Questioninches cm 11 23 34 40.5 56 612 715 818 920 1024 Complete the table below. Worksheet 5

45. Questioncm inches 12.5 25 31.25 46 510 68 715 820 925 1030 Complete the table below. Worksheet 6