Grade 5 · Unit 8: Location and transformation

Enlargements and reductions

Make shapes bigger or smaller by a scale factor.

Photos and posters

A photo can be printed small or large. The picture looks the same – just a different size. This is an enlargement or reduction.

Scale factor 2

A scale factor of 2 doubles every length. The shape stays the same – it is similar. Angles do not change.

Scale factor and area

Double the lengths of a square: 4 times the area. Triple them: 9 times the area. A scale factor of ½ is a reduction.

Models and maps

A model bus at 1 : 50 is 50 times smaller. Multiply by 50 for the real size. 24 cm × 50 = 12 m.

What I learnt

• I can enlarge and reduce shapes by a scale factor.
• I know angles stay the same.
• I can use scale models.