Scales and Ratios

I draw up a plan for a new kitchen. On the plan, 10cm represents 5m in the kitchen.

Write the scale in the form 1 : n

• 10 : 5

• 1 : 0.5

• 1 : 50

• 1 : 500

I have a map of Singapore, with a scale of 1: 30,000.

All 4 options below are correct, but which is the BEST way of thinking about this scale?

• 1mm on the map = 30,000 mm on the ground

• 1km on the map = 30,000km on the ground

• 1m on the map = 30,000m on the ground

• 10cm on the map = 3km on the ground

Using the same map of Singapore, with a scale of 1: 30,000:

On the map, the distance from my flat to Marina Bay Sands is 20cm. How far do I live from MBS?

• 1.5km

• 60km

• 6km

• 6.667 km

Using the same map of Singapore, with a scale of 1: 30,000:

I live 12km from Changi Airport.

What is this distance on the map?

• 40cm

• 36cm

• 25cm

• 18cm

Using the same map of Singapore, with a scale of 1: 30,000:

My local nature park is roughly circular with a radius of 2.5cm.

What is the actual radius of the nature park?

• 75m

• 750m

• 8.33m

A map has a scale 1: 50,000.

Select all of the ratios that are equivalent to this scale:

• 1cm : 500m

• 1m : 50 km

• 2mm : 100m

• 2cm : 1km

The ratio of male to female spectators at a darts tournament is 5 : 3.

1080 people watched the tournament. How many women watched it?

• 360

• 216

• 405

• 648

To make concrete, you have to mix Cement, Sand, Gravel and Water in the ratio 2 : 4 : 6 : 1.

If I need 1040kg of cement, how much Gravel do I need?

• 320 kg

• 480kg

• 173kg

• 600kg

To make concrete, you have to mix Cement, Sand, Gravel and Water in the ratio 2 : 4 : 6 : 1.

If I am using 120kg of cement, how much Concrete am I making?

• 1320kg

• 1560kg

• 780kg

• 7.8 tonnes

To make concrete, you have to mix Cement, Sand, Gravel and Water in the ratio 2 : 4 : 6 : 1.

To 3 s.f., what percentage of concrete is Sand?

• 30.8%

• 40%

• 30.7%

• 33.3%