Question

URGENT!!!!!!
Udin punya 2 buah kubus..perbandingan volume nya V1 : V2 = 8 : 27. JIka V2 = 135 cm3. berapa luas permukaan kubus 1?

Answer 1

V1 : V2 = 8 : 27
V2 = 135

maka
V1 = 8 x 135 / 27 = 8 x 5 = 40 cm³

Sisi kubus  1 = ∛Volume = ∛40 = ∛8x5 = ∛8 x ∛5 = 2∛5

Luas permukaan = 6 x sisi² = 6 x (2∛5)² = 6 x 2² x ∛5² = 6 x 4∛25 = 24∛25 cm²

Jdai Luas permukaannya adalah 24∛25 cm²

Answer 2

V1 = V2 = s1^3 : s2^3 = (2^3) ; (3^3) 
s1 :s2 = 2 : 3
misal s1= 2x dan s2 = 3x
V2 = s2^3 = 27x^3 = 135
x^3 = 5 --> x= ∛5
sisi kubus 1 = s1 = 2x = 2∛5
Volume kubus 1 = (2∛5)³ = 2³ (5) = 40
luas kubus = 6 s²= 6 (4 ∛25)= 24∛25