College

**Term 1, Week 2: Activity 1.14 - Rate**

1. **Solve the following rate problems:**

a) You travel 220 km on 20 litres of petrol. How many km per litre?

b) R144 for 12 tickets. How much per ticket?

c) 560 cars in 8 hours. How many cars per hour?

d) R60 for 6 hours. How much per hour?

e) R15.50 for 5 kg. How much per kg?

f) 35 hours a week (5 days). How many hours per day?

g) 8 patients per 2 hours. How many minutes per patient?

2. **Answer the following questions:**

a) Thami buys [tex]$5 \, \text{l}$[/tex] of paint for R135. What is the cost per litre?

b) Norah is paid R175 per day for working from 09:00 to 16:00. What is she paid per hour?

3. **Calculate the speed or distance:**

a) A car travels 220 km in 2 hours. What is its speed in [tex]$\text{km/h}$[/tex]?

b) If you drive at a constant speed of [tex]$90 \, \text{km/h}$[/tex], what distance will you travel in 3 hours?

c) A taxi travels 120 km in 6 hours. How many km does it travel in 1 hour?

4. **Complete the table for distance covered as time increases at a constant speed of [tex]$120 \, \text{km/h}$[/tex]:**

[tex]\[
\begin{array}{|l|l|l|l|l|l|}
\hline
\text{Time (min)} & 60 \, \text{min} & 90 \, \text{min} & 120 \, \text{min} & 180 \, \text{min} & 240 \, \text{min} \\
\hline
\text{Distance (km)} & & & & & \\
\hline
\end{array}
\][/tex]

5. **Study and complete the table:**

a)
[tex]\[
\begin{array}{|l|l|l|l|l|l|}
\hline
\text{Time (hours)} & 2 \, \text{hours} & 3 \, \text{hours} & 4 \, \text{hours} & 5 \, \text{hours} & 6 \, \text{hours} \\
\hline
\text{Distance (km)} & 180 \, \text{km} & & & & \\
\hline
\end{array}
\][/tex]

b) How fast was the vehicle travelling?

6. **Complete the table for fuel consumption at a speed of [tex]$120 \, \text{km/h}$[/tex] with 10 l of fuel per 100 km:**

[tex]\[
\begin{array}{|l|l|l|l|l|l|}
\hline
\text{Fuel (l)} & & & & & \\
\hline
\text{Distance (km)} & 50 \, \text{km} & 75 \, \text{km} & 100 \, \text{km} & 150 \, \text{km} & 200 \, \text{km} \\
\hline
\end{array}
\][/tex]

Answer :

Sure! Here is a step-by-step solution for each part of the question:

### Part 1: Rate Calculations

1. a) Km per litre:
- You travel 220 km on 20 litres of petrol.
- To find km per litre, divide the distance by the litres:
[tex]\[
\frac{220 \text{ km}}{20 \text{ litres}} = 11 \text{ km/litre}
\][/tex]

1. b) Cost per ticket:
- The total cost is R144 for 12 tickets.
- To find the cost per ticket, divide the total cost by the number of tickets:
[tex]\[
\frac{R144}{12} = R12 \text{ per ticket}
\][/tex]

1. c) Cars per hour:
- 560 cars in 8 hours.
- To find the number of cars per hour, divide the total number of cars by the hours:
[tex]\[
\frac{560 \text{ cars}}{8 \text{ hours}} = 70 \text{ cars/hour}
\][/tex]

1. d) Rands per hour:
- R60 for 6 hours.
- To find the cost per hour, divide the total cost by the hours:
[tex]\[
\frac{R60}{6} = R10 \text{ per hour}
\][/tex]

1. e) Cost per kg:
- R15.50 for 5 kg.
- To find the cost per kg, divide the total cost by the weight in kg:
[tex]\[
\frac{R15.50}{5 \text{ kg}} = R3.10 \text{ per kg}
\][/tex]

1. ก) Hours per day:
- 35 hours a week (5 days).
- To find hours per day, divide the total hours by the number of days:
[tex]\[
\frac{35 \text{ hours}}{5 \text{ days}} = 7 \text{ hours/day}
\][/tex]

1. g) Minutes per patient:
- 8 patients in 2 hours.
- Convert hours to minutes: 2 hours = 120 minutes.
- To find minutes per patient, divide the total minutes by the number of patients:
[tex]\[
\frac{120 \text{ minutes}}{8 \text{ patients}} = 15 \text{ minutes/patient}
\][/tex]

### Part 2: Thami and Norah

2. a) Cost per litre of paint:
- Thami buys 5 litres of paint for R35.
- To find the cost per litre, divide the total cost by the litres of paint:
[tex]\[
\frac{R35}{5 \text{ litres}} = R7.00 \text{ per litre}
\][/tex]

2. b) Norah's pay per hour:
- Norah is paid R175 per day for working from 09:00 to 16:00 (7 hours).
- To find pay per hour, divide the total pay by the number of hours:
[tex]\[
\frac{R175}{7 \text{ hours}} = R25.00 \text{ per hour}
\][/tex]

### Part 3: Speeds and Distances

3. a) Car speed in km/h:
- A car travels 220 km in 2 hours.
- To find the speed in km/h, divide the distance by the time:
[tex]\[
\frac{220 \text{ km}}{2 \text{ hours}} = 110 \text{ km/h}
\][/tex]

3. b) Distance traveled at constant speed:
- Driving at a constant speed of 90 km/h for 3 hours.
- To find the distance traveled, multiply the speed by the time:
[tex]\[
90 \text{ km/h} \times 3 \text{ hours} = 270 \text{ km}
\][/tex]

3. c) Taxi travel distance per hour:
- A taxi travels 120 km in 6 hours.
- To find the distance per hour, divide the distance by the hours:
[tex]\[
\frac{120 \text{ km}}{6 \text{ hours}} = 20 \text{ km/hour}
\][/tex]

### Part 4: Distance over Time Table

- A car travels at a constant speed of 120 km/h.
- To find the distances for given times (in minutes), convert minutes to hours and multiply by speed.

[tex]\[
\begin{align*}
60 \text{ min} & : \frac{60}{60} \times 120 = 120 \text{ km} \\
90 \text{ min} & : \frac{90}{60} \times 120 = 180 \text{ km} \\
120 \text{ min} & : \frac{120}{60} \times 120 = 240 \text{ km} \\
180 \text{ min} & : \frac{180}{60} \times 120 = 360 \text{ km} \\
240 \text{ min} & : \frac{240}{60} \times 120 = 480 \text{ km}
\end{align*}
\][/tex]

### Part 5: Study Table

5. a) Fill in the missing distances:
- A vehicle travels with a constant speed (found in part 5.b):
- For each hour from 2 to 6, add the speed multiplied by time difference to 180 km.

[tex]\[
\begin{align*}
\text{3 hours} & : 180 + (120 \times (3-2)) = 300 \text{ km} \\
\text{4 hours} & : 300 + (120 \times (4-3)) = 420 \text{ km} \\
\text{5 hours} & : 420 + (120 \times (5-4)) = 540 \text{ km} \\
\text{6 hours} & : 540 + (120 \times (6-5)) = 660 \text{ km}
\end{align*}
\][/tex]

5. b) Vehicle Speed:
- The speed of the vehicle can be calculated by using the distance and time (from given initial values):
[tex]\[
\frac{180 \text{ km}}{2 \text{ hours}} = 90 \text{ km/h}
\][/tex]

### Part 6: Fuel Consumption

- Car uses 10 litres per 100 km.
- To find the fuel needed for each distance, multiply the distance by the litre used per 100 km and divide by 100.

[tex]\[
\begin{align*}
50 \text{ km} & : \frac{50 \times 10}{100} = 5 \text{ litres} \\
75 \text{ km} & : \frac{75 \times 10}{100} = 7.5 \text{ litres} \\
100 \text{ km} & : \frac{100 \times 10}{100} = 10 \text{ litres} \\
150 \text{ km} & : \frac{150 \times 10}{100} = 15 \text{ litres} \\
200 \text{ km} & : \frac{200 \times 10}{100} = 20 \text{ litres}
\end{align*}
\][/tex]

I hope this helps you understand how to solve each part step-by-step! If you have any questions or need further clarification, feel free to ask!