1 Herearesomeangles.

a) Sorttheanglesintothetable.

Acuteangle Obtuseangle Rightangle Reflexangle

b) Howdidyoudecidewheretoplaceeachangle?

c) Estimatethesizeofeachangle.

Compareanswerswithapartner.

2 Whatisthesizeofeachangle?Choosethecorrectanswer.

a)

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b)

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c)

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d)

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21° 159°

Lookattheanglesyouhavenotchosen.

Whymightsomebodythinktheyarecorrect?

3 Measurethesizeofeachangleusingaprotractor.

a) b) c)

Measurewithaprotractor

©WhiteRoseMaths2020

A

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d) f) h)

e) g)

4 a) Workoutthesizesoftheangles.

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a

b

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b) Discusswithapartnerhowyouworkedouteachangle.

c) Findthetotalofyourthreeangles.

Whatdoyounotice?

5 Rosieismeasuringthesizeofthisangle.

a)

DoyouagreewithRosie?

Explainyouranswer.

b) Measurethesizeoftheangle.

Measurewithaprotractor

©WhiteRoseMaths2020

I can’t measure it because my protractor doesn’t go that far.

b)

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c)

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d)

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21° 159°

Lookattheanglesyouhavenotchosen.

Whymightsomebodythinktheyarecorrect?

3 Measurethesizeofeachangleusingaprotractor.

a) b) c)