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SCALE CAN BE SHOWN ON A MAP IN THREE WAYS 1. Direct Statement Scale – uses words to describe the relationship between a distance on a map and a specific distance on the Earth’s surface eg. 1 cm to 10 km. If we measure the distance between two places on a map and the distance is 1 cm we know the actual distance between them is 10 km. SCALE CAN BE SHOWN ON A MAP IN THREE WAYS 2. Line Scale is like a special ruler that is divided into units of distance Steps in using line scale: 1. Mark the locations of the two cities on the edge of a sheet of paper 2. Place the edge of the paper against the line scale with the first mark at 0 3. Make a mark on your paper at the right end of the scale 4. Move the mark from step 3 (above) to 0 on the on the line scale at measure the remaining distance SCALE CAN BE SHOWN ON A MAP IN THREE WAYS 3. Representative Fraction (R.F.) Scale – this is a ratio and is shown as 1:50 000. It means that one unit on the map represents 50 000 of the same units on the Earth’s surface. The units may be in centimeters or inches. Eg. If the R.F. is 1:50 000 then 1 cm on the map represents 50 000 cm on the Earth’s surface. SCALE CAN BE SHOWN ON A MAP IN THREE WAYS To convert an R.F. to a direct statement scale, divide the denominator by 100 000, to change the centimeters into kilometer. Eg. R.F. 1:50 000 is 1 cm = 50 000 cm 1 cm = (50 000 / (divided by) 100 000) km 1 cm = 0.5 or 1 cm to 500 m ( half a km) To convert Direct Statement Scale to R.F. Scale, multiply the number of kilometers by 100 000 Eg. Convert the direct statement 1 cm to 2.5 km into a representative fraction: 1 cm = 2.5 km 1 cm = (2.5 x 100 000) cm 1 cm = 250 000 cm or 1:250 000