Perhatikan gambar berikut!​

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Perhatikan gambar berikut!​

Perhatikan gambar berikut!​

Luas permukaan bola = sf 4~times~pi~times~{r_{bola}}^2

sf 150~=~4~times~pi~times~{r_{bola}}^2

color{darkred}sf {r_{bola}}^2~=~frac{150}{4pi}

color{darkred}sf r_{tabung}~=~r_{bola}

color{darkred}sf t_{tabung}~=~2~times~r_{bola}

Luas alas & tutup tabung :

sf L_1~=~2~times~pi~times~{r_{tabung}}^2

sf L_1~=~2~times~pi~times~{r_{bola}}^2

sf L_1~=~2pi~times~frac{150}{4pi}

purple{sf L_1~=~75~cm^2}

Luas selimut tabung :

sf L_2~=~keliling~alas~tabung~times~tinggi~tabung

sf L_2~=~2~times~pi~times~r_{tabung}~times~t_{tabung}

sf L_2~=~2~times~pi~times~r_{bola}~times~2~times~r_{bola}

sf L_2~=~4pi~times~{r_{bola}}^2

sf L_2~=~4pi~times~frac{150}{4pi}

purple{sf L_2~=~150~cm^2}

Luas seluruh permukaan tabung = sf L_1~+~L_2

Luas seluruh permukaan tabung = 75 + 150

Luas seluruh permukaan tabung = pink{sf 225~cm^2}

to~(~red{bold{C}}~)