Mastering Math Operations: Indonesian Examples

1. Cost of Rice — Calculate the cost of the rice by multiplying the mass of rice by the price per kg.
   $$C_{\text{rice}}=m_{\text{rice}}imes{p}_{\text{rice}}=3imes15000=45000extIDR$$
2. Cost of Sugar — Calculate the cost of the sugar by multiplying the mass of sugar by the price per kg.
   $$C_{\text{sugar}}=m_{\text{sugar}}imes{p}_{\text{sugar}}=2imes20000=40000extIDR$$
3. Total Cost — Add the cost of the rice and the cost of the sugar to find the total cost.
   $$C_{\text{total}}=C_{\text{rice}}+C_{\text{sugar}}=45000+40000=85000extIDR$$

$$85000extIDR$$

→ The total cost is 85,000 IDR.

1. Formula — The formula to calculate time is time = distance / speed.
   $$t=\frac{d}{v}$$
2. Perhitungan — Plug in the values for distance and speed.
   $$t=\frac{150}{80}=1.875exthours$$

$$1.875exthours$$

→ The time taken for the journey is 1.875 hours.

1. Profit per Portion — Calculate the profit per portion by subtracting the cost per portion from the selling price per portion.
   $$P_{\text{portion}}=P_{\text{selling}}-C_{\text{cost}}=20000-10000=10000extIDR$$
2. Total Profit — Calculate the total profit by multiplying the profit per portion by the number of portions sold.
   $$P_{\text{total}}=P_{\text{portion}}imesn=10000imes50=500000extIDR$$

$$500000extIDR$$

→ The total profit is 500,000 IDR.

1. Total Distance — Add the distance from Jakarta to Yogyakarta and the distance from Yogyakarta to Bali.
   $$d_{\text{total}}=d_1+d_2=500+900=1400extkm$$
2. Verifikasi — The total distance is in kilometers, and the calculation is dimensionally correct.

$$1400extkm$$

→ The total distance traveled is 1,400 km.

1. Cost per Person — Divide the total cost of the meal by the number of people.
   $$C_{\text{person}}=\frac{C_{\text{total}}}{n}=\frac{200000}{4}=50000extIDR$$
2. Verifikasi — The cost per person is in IDR, and the calculation is dimensionally correct.

$$50000extIDR$$

→ The cost per person is 50,000 IDR.

1. Total Cost — Add the cost of flights, accommodation, and activities.
   $$C_{\text{total}}=C_{\text{flights}}+C_{\text{accommodation}}+C_{\text{activities}}=3000000+2000000+1500000=6500000extIDR$$
2. Verifikasi — The total cost is in IDR, and the calculation is dimensionally correct.

$$6500000extIDR$$

→ The total cost of the vacation is 6,500,000 IDR.

1. Formula — The formula to calculate time is time = distance / speed.
   $$t=\frac{d}{v}$$
2. Perhitungan — Plug in the values for distance and speed.
   $$t=\frac{700}{70}=10exthours$$

$$10exthours$$

→ The time taken for the journey is 10 hours.

1. Cost of Notebooks — Calculate the cost of the notebooks by multiplying the number of notebooks by the price per notebook.
   $$C_{\text{notebooks}}=n_{\text{notebooks}}imes{p}_{\text{notebook}}=3imes5000=15000extIDR$$
2. Cost of Pens — Calculate the cost of the pens by multiplying the number of pens by the price per pen.
   $$C_{\text{pens}}=n_{\text{pens}}imes{p}_{\text{pen}}=2imes3000=6000extIDR$$
3. Cost of Textbook — Calculate the cost of the textbook by multiplying the number of textbooks by the price per textbook.
   $$C_{\text{textbook}}=n_{\text{textbook}}imes{p}_{\text{textbook}}=1imes20000=20000extIDR$$
4. Total Cost — Add the cost of the notebooks, pens, and textbook to find the total cost.
   $$C_{\text{total}}=C_{\text{notebooks}}+C_{\text{pens}}+C_{\text{textbook}}=15000+6000+20000=41000extIDR$$

$$41000extIDR$$

→ The total cost is 41,000 IDR.

1. Profit per Piece — Calculate the profit per piece of batik by subtracting the cost per piece from the selling price per piece.
   $$P_{\text{piece}}=P_{\text{selling}}-C_{\text{cost}}=100000-50000=50000extIDR$$
2. Total Profit — Calculate the total profit by multiplying the profit per piece by the number of pieces sold.
   $$P_{\text{total}}=P_{\text{piece}}imesn=50000imes30=1500000extIDR$$

$$1500000extIDR$$

→ The total profit is 1,500,000 IDR.

1. Total Distance — Add the distance from Jakarta to Bandung and the distance from Bandung to Yogyakarta.
   $$d_{\text{total}}=d_1+d_2=150+400=550extkm$$
2. Verifikasi — The total distance is in kilometers, and the calculation is dimensionally correct.

$$550extkm$$

→ The total distance traveled is 550 km.

1. Cost per Person — Divide the total cost of the meal by the number of people.
   $$C_{\text{person}}=\frac{C_{\text{total}}}{n}=\frac{300000}{5}=60000extIDR$$
2. Verifikasi — The cost per person is in IDR, and the calculation is dimensionally correct.

$$60000extIDR$$

→ The cost per person is 60,000 IDR.