Question

a supra 2 = b supra 4 = c supra 5. a x b x c =320 a =? b =? c =?

Answer 1

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Answer 2

a / 2 = b / 4 = c / 5  ⇒ 4 a = 2 b ⇒ a = 2 b / 4 = b / 2 

2 c = 5 a ⇒ c = 5 a / 2 = ( 5 × b / 2 ) : 2 = 5 b / 4 

a × b × c = 320 

(b / 2)  × b × ( 5 b / 4) = 320 

5 b ³ / 8 = 320 ⇒  5 b ³ = 320 × 8  ⇒ b ³ = 2560 : 5 = 512  ⇒ b = 8 

a = 8 / 2 = 4 

c = ( 5 × 4) / 2 = 20 / 2 = 10 

Verific:    4 × 8 × 10 = 320 
            4/2 = 8/4 = 10 / 5 = 2