Rates and Ratios

Question 1

Define

Rate

Answer 1

A comparison of amounts with different units. As the units are different, they must be specified.

Question 2

How do you simplify a rate?

Answer 2

A rate is written as some amount per a second amount. This makes simplifying rates very easy - you simply divide both amounts by whatever the second is.

Question 3

1J/s =

Answer 3

1W

Question 4

Solve

Fuel Consumption =

Answer 4

Amount of fuel (L) × 100 / Distance travelled (km)

Question 5

How do you divide a quantity into a ratio?

Answer 5

1. Find the total number of parts by adding all the terms in the ratio together.
2. Divide the quantity by this total. This gives the unit value.
3. Multiply this unit value by each ratio term.
4. (Optional) Add all your answers together to check.

Question 6

How do you calculate a watt-hour (Wh)

Answer 6

It is the wattage used multiplied by the number of hours the device was turned on. For example a 20W globe used for 10 hours uses 200Wh.

Question 7

Define

Similar figures

Answer 7

Figures with corresponding angles that are equal and corresponding sides that are in the same ratio.

Question 8

Define

Corresponding sides/angles

Answer 8

Being in the same positions relative to each other on the diagram.

Question 9

Define

Plan

Answer 9

A view of an object as seen from above.

Question 10

Define

Elevation

Answer 10

A view of an object from the side.

Question 11

When is the capture-recapture technique used?

Answer 11

It is used to estimate populations, when it is not possible to conduct a census.