# Angle and Factors

Topics: Angle, Elementary number theory, Division Pages: 6 (1464 words) Published: December 18, 2012
STUDENT REPORT
27 August 2012
Duration 40 mins | Examcode 6169451

Multiples and Lines and Angles

Factors;

SCHOOL

CLASS 5

DIVISION D

STUDENT

VORA CHAITYA NIRAV

ROLL NO 25

YOUR PERFORMANCE IN THE TEST: 81.82% The class average performance in this topic is 68.8% BEST PERFORMANCE IS IN SUBTOPIC Understanding of factors and multiples TWO SUB TOPICS RECOMMENDED FOR IMPROVEMENT * Understanding of lines * Understanding of angles.

1

DA STUDENT REPORT

CLASS 5 ROLL NO 25

Multiples and Factors; Lines and Angles

DATE 27 August 2012

Misconceptions Concept: Application of HCF in Real Life
10

Q Reema has 3 pieces of ribbon which are 18 m, 36 m and 45 m long respectively. She wants to cut them into pieces of equal length. She wants to do this in such a way that no ribbon is wasted. What is the length of the LONGEST piece that she can get? 1 3m 2 6m 3 9m 4 15 m

Correct Option: 3

Student Selection: 1

Students who have answered A seem to have realised that the required length should be a common factor of 18, 36 and 45. But they seem to have opted for the common factor that is clearly visible, and have not thought beyond the obvious. It is also possible that they have not noticed the word longest in the question, or may not have realised that they have to find the HCF here. Students answering incorrectly are unable to apply their understanding of common factors to the given situation. Students may also be blindly relating words like largest, greatest or maximum with HCF and shortest, least or minimum with LCM. Remedial measure: Pose the question and ask the following. Ensure each student has understood the question. - If a 18 m long ribbon is to be cut into pieces of equal length, what are all possible lengths of a piece of ribbon? (Students are expected to answer as 2 m, 3 m, 6 m, and 9 m. Help them see that all these are nothing but the factors of 18.) - If a 36 m long ribbon is to be cut into pieces of equal length, what are all possible lengths of a piece of ribbon? (Students are expected to answer as 2 m, 3 m, 4 m, 6 m, 9 m, 12 m. Help them see that all these are factors of 36.) If a 45 m long ribbon is to be cut into pieces of equal length, what are all possible lengths of a piece of ribbon? (Students are expected to answer as 3 m, 5 m, 9 m and 15 m. Help them see that all these are factors of 45. - Ask students about all the possible lengths of a piece of a ribbon if the ribbons 18 m, 36 m and 45 m long are cut to get the pieces of same length. (Students are expected to come up with the answers as 3 m, 6 m and 9 m. Help them see that all these are common factors of 18, 36 and 45. If they are supposed to cut both the ribbons into pieces of equal length and get the longest possible pieces, what could the length of the piece be? Help them see that it is 9 m which is the HCF of 18, 36 and 45. Pose more of such problems involving applications of HCF.

2

DA STUDENT REPORT

CLASS 5 ROLL NO 25

Multiples and Factors; Lines and Angles

DATE 27 August 2012

Concept: Identifying a Right Angle Q In which of these figures, is/are the angle shown a right angle? 17

1 3

only in figure 1 only in figures 1, 2 and 3 Student Selection: 2

2 4

only in figures 1 and 3 In all figures - 1, 2, 3 and 4

Correct Option: 4

Students who have answered A may have felt that the angle changes when the angle is turned. Students who have answered B and C are able to identify a right angle only when one of its arms is horizontal and the other vertical. Students who have answered incorrectly are not able to identify a right angle in non standard orientations. Remedial measure: Help students understand angle as an amount of turn - by how much should one arm be rotated so that it coincides with the other. Help them understand that this does not change when the figure as a whole is rotated. Ask them to spot out the right angles around them - in the corner of...