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Scale Ratios. Interpreting Scale Diagrams. Reading Maps and Scale Diagrams is an important life skill. The key is understanding ratios. Every map or architectural drawing uses scales or ratios. This means that they are an exact smaller version of the real thing.
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Scale Ratios Interpreting Scale Diagrams
Reading Maps and Scale Diagrams is an important life skill. The key is understanding ratios. • Every map or architectural drawing uses scales or ratios. This means that they are an exact smaller version of the real thing. • Without knowing the scale, a map or drawing cannot be interpreted.
Notice the scale of the map. With this kind of scale, you can use a ruler and compare it to the scale, to find out approximately how many miles or kilometers it is fromone place to another Measure with a ruler the distance from one place to another Compare to the scale. Make an estimate from the scale.
Using this method, estimate the distance from: • Grand Falls to Hartland • Boiestown to Doaktown • Saint John to Fredericton • Dalhousie to St. George Sometimes we use the expression, “as the crow flies” which means a straight line. Find the distance “as the crow flies.”
Using the scale of the house plan, calculate the area of each room. The scale is 4 blocks : 1 meter So 4:1 A = length x width A = 3.25 m x 3.25 m A = 10.5625 m2 Count the number of blocks in the bottom right bedroom Set up a ratio 4 :1 = 13 : ϰ 3.25 m Rewrite as fractions and cross multiply ϰ = 3.25 m 3.25 m Now do the same for the length of the room 4 : 1 = 13 : ϰ Rewrite as a fraction and cross multiply. ϰ = 3.25 m
Help with Lounge Separate the lounge into two rectangles and then add the two. ϰ=5 m Count the blocks across the room and set up a ratio using the scale B 20 blocks Now do the same for the length of the room M Cross Multiply B ϰ=5 m M ϰ=4.25 m Cross Multiply Area = 21.25 m2 ϰ=4.25 m You have now found the length and width of this part of the room. Area = Length x Width Area = 5 m x 4.25 m Area = 21.25 m2 B Remember the scale is 4 blocks : 1 metre M
Now do the same for this part of the lounge. Once you find the area, you add the two parts to find the total area of the room 12 blocks 13 blocks Calculate the length and width of the room using ratios and use A=LxW Then add the two parts of the room to get the area of the room.
Advanced Skills 1.If the walls are 1.3 meters high, and you ignore doors and windows, how many cans of paint will it take to paint the three bedrooms if 4 litres of paint are required to cover 9m2? Remember that you cannot buy cans of paint smaller than 4 litres. 2.How much will it cost if a 4 litre can of paint costs $35.97?