Di sebuah tempat parkir terdapat 48 kendaraan berupa mobil (4 roda) dan sepeda motor (2 roda). Setelah dihitung, jumlah roda seluruh kendaraan yang terparkir berjumlah 144 roda. Biaya parkir sebuah mobil adalah Rp8.000,00 sedangkan biaya parkir sepeda motor adalah Rp5.000,00, total penghasilan pengelola parkir jika hari itu tidak ada lagi kendaraan lain yang masuk adalah..... A. Rp 312.000,00 B. Rp 336.000,00 C. Rp 364.000,00 D. Rp 376.000,00

<p>Misalkan :</p><ul><li>x = mobil</li><li>y = motor</li></ul><p>Maka persamaan matematikanya menjadi :</p><p>x + y = 48 &nbsp;----&gt; x = 48 - y &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (1)</p><p>4x + 2y = 144 &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; (2)</p><p>&nbsp;</p><p>Substitusikan x = 48 - y ke persamaan (2)</p><p>4x + 2y = 144&nbsp;</p><p>4(48 - y) + 2y = 144</p><p>192 - 4y + 2y = 144</p><p>192 - 2y = 144</p><p>192 - 144 = 2y</p><p>48 = 2y</p><p>y = 48 : 2 = 24</p><p>Banyaknya motor = 24</p><p>&nbsp;</p><p>Substitusikan y = 24 ke persamaan (1)</p><p>x = 48 - y</p><p>&nbsp; &nbsp;= 48 - 24</p><p>&nbsp; &nbsp;= 24&nbsp;</p><p>&nbsp;</p><p>Total penghasilan = 8000x + 5000y</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 8000(24) + 5000(24)</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= 192.000 + 120.000</p><p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;= Rp. 312.000;</p><p>Jadi pendapatan pengelora parkir adalah Rp. 312.000;</p><p>&nbsp;</p><p>Jawaban : <strong>A</strong></p>