Second Term Lesson Note for Week Three
Class : JSS 1
Subject : Mathematics
Topic : Approximation involving basic operations
Duration : 80 Minutes
Period : Double Period
Reference Book :
Essential Mathematics for Junior Secondary School, Book 1 (JSS 1).
Lagos State Unified schemes of work for Junior Secondary School, JSS 1 – 3.
Online Resources
Instructional Material :
Learning Objectives : By the end of the lesson student will be able to :
i. Perform addition and subtraction using approximation.
ii. Solve problems on multiplication and division using approximation.
Content :
ADDITION AND SUBTRACTION OF APPROXIMATIONS
Example 3.1: approximate the following to it accuracy of degree
I. 674 + 975 (3 s.f)
II. 805 + 912 (4s.f)
III. 3076 – 621 (2 s.f)
IV. 695.728 – 97.979 (4 s.f)
SOLUTIONS :
I. 674 + 975 = 1649 (1650 to 3 s.f.) note that you must add the numbers before converting to the degree.
II. 805 + 912 = 1717 (1717 to 4s.f.)
III. 3076 – 621 = 2455 (2500 to 2 s.f.)
IV. 695.728 – 97.979 = 597.749 (597.7 to 4 s.f.)
EVALUATION:
Convert the following to their accuracy degree
1.) 42.4739 to 5 s.f
2.) 67.3258 to 3s.f
3.) 879.9087 to 4 s.f
4.) 304.385 to 5 s.f
ASSIGNMENT:
ESSENTIAL MATHEMATICS BOOK 1
EXERCISE 8.7 No. 1 (g,h,I,j,k,l and m) PAGE 93
EXERCISE 8.8 No. 7,8 and 9 PAGE 95
EXERCISE 8.5 NO 1(D,E,F), NO 4 (B &C) No. 5 (A TO G) PAGE 89