Contents

## Selina Concise Mathematics Class 6 ICSE Solutions Chapter 24 Angles (With their Types)

**Selina Publishers Concise Mathematics Class 6 ICSE Solutions Chapter 24 Angles (With their Types)**

### Angles Exercise 24A – Selina Concise Mathematics Class 6 ICSE Solutions

Question 1.

For each angle given below, write the name of the vertex, the names of the arms and the name of the angle.

Solution:

Question 2.

Name the points :

(i) in the interior of the angle PQR,

(ii) in the exterior of the angle PQR.

Solution:

Question 3.

In the given figure, figure out the number of angles formed within the arms OA and OE.

Solution:

Question 4.

Add :

(i) 29° 16′ 23″ and 8° 27′ 12″

(ii) 9° 45’56” and 73° 8′ 15″

(m) 56° 38′ and 27° 42’30”

(iv) 47° and 61° 17’4″

Solution:

Question 5.

In the figure, given below name :

(i) three pairs of adjacent angles.

(ii) two acute angles,

(iii) two obtuse angles

(iv) two reflex angles.

Solution:

Question 6.

In the given figure ; PQR is a straight line. If :

(i) ∠SQR = 75° ; find ∠PQS.

(ii) ∠PQS = 110°; find ∠RQS

Solution:

Question 7.

In the given figure ; AOC-is a straight line. If angle AOB = 50°, angle AOE = 90° and angle COD = 25° ; find the measure of :

(i) angle BOC

(ii) angle EOD

(iii) obtuse angle BOD

(iv) reflex angle BOD

(v) reflex angle COE.

Solution:

Question 8.

In the given figure if :

(i) a = 130° ; find b.

(ii) b = 200 ; find a.

(iii) a = 5/3 right angle, find b

Solution:

Question 9.

In the given diagram, ABC is a straight line.

(i) If x = 53°, find y.

(ii) If y =1\(\frac { 1 }{ 2 }\) right angles ; find x.

Solution:

Question 10.

In the given figure, AOB is a straight line. Find the value ofx and also answer each of the following :

(i) ∠AOP = ……..

(ii) ∠BOP = ……..

(iii) which angle is obtuse ?

(iv) which angle is acute ?

Solution:

Question 11.

In the given figure, PQR is a straight line. Find x. Then complete the following:

(i) ∠AQB = ……..

(ii) ∠BQP = ……..

(iii) ∠AQR = …….

Solution:

Question 12.

In the given figure, lines AB and CD intersect at point O.

(i) Find the value of ∠a.

(ii) Name all the pairs of vertically opposite angles.

(iii) Name all the pairs of adjacent angles.

(iv) Name all the reflex angles formed and write the measure of each.

Solution:

Question 13.

In the given figure :

(i) If ∠AOB = 45°, ∠BOC = 30° and ∠AOD= 110°;

find : angles COD and BOD.

(ii) If ∠BOC = ∠DOC = 34° and ∠AOD = 120° ;

find : angle AOB and angle AOC.

(iii) If ∠AOB = ∠BOC = ∠COD = 38°

find : reflex angle AOC and reflex angle AOD.

Solution:

### Angles Exercise 24B – Selina Concise Mathematics Class 6 ICSE Solutions

Question 1.

Write the complement angle of :

(i) 45°

(ii) x°

(iii) (x – 10)°

(iv) 20° + y°

Solution:

Question 2.

Write the supplement angle of :

(i) 49°

(ii) 111°

(iii) (x – 30)°

(iv) 20° + y°

Solution:

Question 3.

Write the complement angle of :

Solution:

Question 4.

Solution:

Question 5.

Find the angle :

(i) that is equal to its complement ?

(ii) that is equal to its supplement ?

Solution:

Question 6.

Two complementary angles are in the ratio 7 : 8. Find the angles.

Solution:

Question 7.

Two supplementary angles are in the ratio 7 : 11. Find the angles.

Solution:

Question 8.

The measures of two complementary angles are (2x – 7)° and (x + 4)°. Find x.

Solution:

Question 9.

The measures of two supplementary angles are (3x + 15)° and (2x + 5)°. Find x.

Solution:

Question 10.

For an angle x°, find :

(i) the complementary angle

(ii) the supplementary angle

(iii) the value of x° if its supplementary angle is three times its complementary angle.

Solution:

### Angles Revision Exercise – Selina Concise Mathematics Class 6 ICSE Solutions

Question 1.

Explain what do you understand by :

(i) Adjacent angles ?

(ii) Complementary angles ?

(iii) Supplementary angles ?

Solution:

Question 2.

Find the value of ‘x’ for each of the following figures :

Solution:

Question 3.

Find the number of degrees in an angle that is (i) \(\frac { 3 }{ 5 }\) of a right angle (ii) 0.2 times of a straight line angle.

Solution:

Question 4.

In the given figure; AB, CD and EF are straight lines. Name the pair of angles forming :

(i) straight line angles.

(ii) vertically opposite angles.

Solution:

Question 5.

Find the complement of :

Solution:

Question 6.

Find the supplement of :

Solution:

Question 7.

Two complementary angles are in the ratio 8 : 7. Find the angles.

Solution:

Question 8.

Two supplementary angles are in the ratio 7 : 5. Find the angles.

Solution:

Question 9.

Two supplementary angles are (5x – 82°) and (4x + 73°). Find the value of x.

Solution:

Question 10.

Find the angle formed by the arms of a clock at:

(i) 3 O’clock

(ii) 6 O’clock

(iii) 9 O’clock

(iv) 12 O’clock

Solution:

Question 11.

For an angle y°, find :

(i) its supplementary angle.

(ii) its complementary angle.

(iii) the value of y° if its supplement is four times its complement.

Solution:

Question 12.

Use the adjoining figure to find :

(i) ∠BOD

(ii) ∠AOC

Solution:

Question 13.

Two adjacent angles forming a linear pair are in the ratio 7:5, find the angles.

Solution:

Question 14.

Find the angle that is three times its complementary angle.

Solution:

Question 15.

An angle is one-thirds of a straight line angle ; find :

(i) the angle

(ii) the complement and the supplement of the angle obtained above.

Solution: