Ayah ingin membuat model balok padat yang terbuat dari bahan gypsum dengan luas alas 200 cm² dan tingginya 9 cm. Harga gypsum per liter adalah Rp15.000,00. Biaya minimal yang harus ayah keluarkan untuk membuat model balok tersebut adalah... A. Rp 30.000,00 B. Rp 27.000,00 C. Rp 25.000,00 D. Rp 20.000.00

<p>Jawaban: B</p><p>&nbsp;</p><p>Ingat:</p><p>Volume = luas alas × tinggi</p><p>1 dm³ = 1 liter</p><p>&nbsp;</p><p>Pembahasan:</p><p>Volume balok = luas alas × t</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 200 × 9</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1.800 cm³</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1.800/1.000 dm³</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1,8 dm³</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 1,8 liter.</p><p>&nbsp;</p><p>Biaya minimal = 1,8 × 15.000 = 27.000</p><p>&nbsp;</p><p>Jadi, jawaban yang benar B.</p>