MATHS!!!!!

[libra94]

i jst need to know abt the map scale............are the units always converted to centimeters unless told in the ques.??
e.g. ratio of a model car : a real car
1 : 200 (is it in cm??)
1)find the area of the real car window when the area for the model window is 20cm2
so (1x1) : (200x200)
20 : X
so we cross multiply to gt the area for the real car window(X)
so is the answer in cm????

 

[user]

see a ratio has no units if for any distance or length it can be any possible unit km m cm but it will have the same units for both quantities for eg for the ratio 1:200 if u need ur ans. in metres consider the ratio being in metres and if u want it in cm then take ur ratio to be in cm.Let me proof it say if u think ratio 1:200 is in metres then try finding the ratio in cm I hope u know we multiply by 100 to convert m to cm so in cms it will be 100:20000 Since ratio should always be in simplest forms simplify it and u get 1:200!!!Do u get it no matters To find ratio dont forget to square ratio of length..since unit for area is m2 or cm2... hope that helps if still confused let me know