Kerala Syllabus Class 6 Mathematics - Unit 1 Angles - Questions and Answers | Teaching Manual 

Questions and Answers for Class 6 Mathematics - Unit 1 Angles - Study Notes | Text Books Solution STD 6 - Maths: Unit 1 Algebra - Questions and Answers | ഗണിതം - കോണുകൾ - ചോദ്യോത്തരങ്ങൾ 

ആറാം ക്ലാസ്സ്‌  Mathematics - Unit 1 Angles എന്ന പാഠം ആസ്പദമാക്കി തയ്യാറാക്കിയ ചോദ്യോത്തരങ്ങള്‍. ഈ അധ്യായത്തിന്റെ Teachers Handbook, Teaching Manual എന്നിവ ഡൗൺലോഡ് ചെയ്യാനുള്ള ലിങ്ക് ചോദ്യോത്തരങ്ങളുടെ അവസാനം നൽകിയിട്ടുണ്ട്. പുതിയ അപ്‌ഡേറ്റുകൾക്കായി ഞങ്ങളുടെ Telegram Channel ൽ ജോയിൻ ചെയ്യുക.

Kerala Syllabus STD 6 Maths: Unit 1 Angles - Textbook Solutions

♦ Textbook Activities (Textbook Page No: 13)
Drawing angles
(1) Measure and mark each angle below:
Answer:
(2) Draw the pictures below in the notebook:
Answer:
(A) How to draw?
First, draw a horizontal line of length 4 cm. Use a protractor to mark 50° angle at each end of the horizontal line. Draw a line from each endpoint of the base, extending along the 50° angle until the two lines meet.
(B) How to draw?
Draw a horizontal line segment 5 cm long. At the end of the line, draw an angle 30° at its left end and draw an angle 90° (right angle) at its right end. 
(C) How to draw?
Draw a horizontal line 6 cm long. At each end of the line, use a protractor to mark a 20° angle on both sides of the line. From each end of the line, draw lines along the 20° marks until they intersect. In the same way, mark 20° angle at the bottom left of the line and a 20° angle at the bottom right of the line. The protractor should be turned so that the horizontal line on the protractor are aligned with the first line, and the measuring part is facing down, as in the figure below. Join them.
(D) How to draw?
First, draw a horizontal line, 5 cm long. Mark an angle of 60° to the left of the line and mark a distance of 3 cm from it. Mark an angle 120° to the right of the first line and mark a distance of 3 cm from it. Join these distances. Then you get a line of length 5 cm.

♦ Textbook Activities (Textbook Page No: 17, 18)
Circle division
(1)  In each of  the pictures below, calculate what fractions of  the circle are the yellow and green parts:
Answer:
(A) Total measure of angles at the centre = 360°
Measure of the yellow-coloured angle = 20°
Measure of the green-coloured angle = 360° − 20° = 340°
Yellow coloured part = ²⁰⁄₃₆₀ = ¹⁄₁₈
Green coloured part = ³⁴⁰⁄₃₆₀ = ¹⁷⁄₁₈

(B) Total measure of angles at the centre = 360°
Measure of the yellow-coloured angle = 24°
Measure of the green-coloured angle = 360° − 24° = 336°
Yellow coloured part = ²⁴⁄₃₆₀ = ¹⁄₁₅
Green coloured part = ³³⁶⁄₃₆₀ = ¹⁴⁄₁₅

(C) Total measure of angles at the centre = 360°
Measure of the yellow-coloured angle = 54°
Measure of the green-coloured angle = 360° − 54° = 306°
Yellow coloured part = ⁵⁴⁄₃₆₀ = ³⁄₂₀
Green coloured part = ³⁰⁶⁄₃₆₀ = ¹⁷⁄₂₀

(D) Total measure of angles at the centre = 360°
Measure of the yellow-coloured angle = 80°
Measure of the green-coloured angle = 360° − 80° = 280°
Yellow coloured part = ⁸⁰⁄₃₆₀ = ²⁄₉
Green coloured part = ²⁸⁰⁄₃₆₀ = ⁷⁄₉

(E) Total measure of angles at the centre = 360°
Measure of the yellow-coloured angle = 108°
Measure of the green-coloured angle = 360° − 108° = 252°
Yellow coloured part = ¹⁰⁸⁄₃₆₀ = ³⁄₁₀
Green coloured part = ²⁵²⁄₃₆₀ = ⁷⁄₁₀

(F) Total measure of angles at the centre = 360°
Measure of the yellow-coloured angle = 150°
Measure of the green-coloured angle = 360° − 150° = 210°
Yellow coloured part = ¹⁵⁰⁄₃₆₀ = ⁵⁄₁₂
Green coloured part = ²¹⁰⁄₃₆₀ = ⁷⁄₁₂

(2) Mark each of the fractions below as part of a circle and colour the pictures.
(i) ⅜  (ii) ⅖  (iii) ⁴⁄₉  (iv) ⁵⁄₁₂  (v) ⁵⁄₂₄
Answer:
(i) ⅜  
Total measure of angles at the centre = 360°
⅛ part of 360° = 360° x ⅛ = 45°
∴ ⅜ part of the circle = 45° x 3 = 135°

(ii) ⅖ 
Total measure of angles at the centre = 360°
⅕ part of 360° = 360° x ⅕ = 72°
∴ ⅖ part of the circle = 72° x 2 = 144°

(iii) ⁴⁄₉ 
Total measure of angles at the centre = 360°
⅑ part of 360° = 360° x ⅑ = 40°
∴ ⁴⁄₉ part of the circle = 40° x 4 = 160°

(iv) ⁵⁄₁₂
Total measure of angles at the centre = 360°
¹⁄₁₂ part of 360° = 360° x ¹⁄₁₂ = 30°
∴ ⁵⁄₁₂ part of the circle = 30° x 5 = 150°

(v) ⁵⁄₂₄
Total measure of angles at the centre = 360°
¹⁄₂₄ part of 360° = 360° x ¹⁄₂₄ = 15°
∴ ⁵⁄₂₄ part of the circle = 15° x 5 = 75°

Draw the pictures below:
(i) To draw a pentagon, first draw a circle with any radius. Measure the angle 360 ÷ 5 = 72° at the centre of the circle and draw 5 radii to divide the
circle into 5 equal parts. Connect the ends of the radii. Erase the drawn circle and the radii. Now you get the Pentagon. Connect each corner of this figure with the 2 opposite corners. Now make it beautiful by giving suitable colours.

(ii) Draw a circle with any radius. Mark 5 dots on the circle at equal distances. Connect each of these dots with 2 dots on the circle in opposite positions. Then you get a figure. Now you need to draw the inner star. For this, connect the above lines from each point where they meet with the 2 dots in the opposite position where they meet. Now erase the unnecessary parts, and we get the figure. Colour it and make it beautiful.

(iii) Here, we have to draw a regular octagon. For this first, draw a circle with any radius. Measure 45° from the 360 ÷ 8 = 45° from the centre of the circle and mark 8 points on the circle at equal distances. Connect these. Erase the circle. After that, each point is connected to the opposite point. Now it becomes the figure. Colour it and make it beautiful.

(iv) Draw two lines vertically and another line perpendicular to them. Join the ends of the vertical line drawn now so that it forms a 60° angle with the first vertical line. Now, if you draw lines vertically downwards from each corner and join their ends, you will get the figure. Colour it and make it beautiful.