Determine if the follow ratios form a proportion. Also, write the middle terms and extreme terms where the ratio forms a proportion.

(a) 25 cm : 1 m and Rs. 40 : Rs. 160


(b) 39 litres : 65 litres and 6 bottles : 10 bottles


(c) 2 kg : 80 kg and 25 g : 625 g


(d) 200 mil : 2.5 litres and Rs. 4 : Rs. 50

(a) At first,


25cm = m


= 0.25


Now,


We can check this as follows,



And,



Therefore,


45 : 60 = 12 : 15


Hence,


We can clearly observe that,


They are in proportion.


Thus,


Middle terms are 1m, Rs 40


And,


Extreme terms are 25cm, Rs 160.


(b) At first,


We have to check if they are in proportion.


Now,


We can check this as follows,



And,



Therefore,


39:65 = 6 : 10


Hence,


We can clearly observe that,


They are in proportion.


Thus,


Middle terms are 75 l, Rs 10


And,


Extreme terms are 39cm, Rs 10.


(c) At first,


We have check if they are in proportion:


Now,


We can check this as follows,



And,



Therefore,


2 : 80 ≠ 25 : 625


Hence,


We can clearly observe that,


They are in proportion.


(d) At first,


1l =


2.5l = 2500 ml


Now,


We can check this as follows,



And,



Therefore,


200: 2500 = 4 : 50


Hence,


We can clearly observe that,


They are in proportion.


Thus,


Middle terms are 2.5l, Rs 4


And,


Extreme terms are 200ml, Rs 50


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