(a) Without using Mathematical tables or calculators, simplify: \(3\frac{4}{9} \div (5\frac{1}{3} - 2\frac{3}{4}) + 5\frac{9}{10}\) (b) A number is selected...

Assessment: WAEC SSCE - General Mathematics - 2015 (Essay) Subject: General Mathematics

Question 1 Report

(a)  Without using Mathematical tables or calculators, simplify:

\(3\frac{4}{9} \div (5\frac{1}{3} - 2\frac{3}{4}) + 5\frac{9}{10}\)

(b) A number is selected at random from each of the sets {2, 3, 4} and {1, 3, 5}. Find the probability that the sum of the two numbers is greater than 3 and less than 7.

Answer Details

(a) Brackets first:

\[5\tfrac{1}{3} - 2\tfrac{3}{4} = \tfrac{16}{3} - \tfrac{11}{4} = \tfrac{64 - 33}{12} = \tfrac{31}{12}\] \[3\tfrac{4}{9} \div \tfrac{31}{12} = \tfrac{31}{9} \times \tfrac{12}{31} = \tfrac{12}{9} = \tfrac{4}{3}\] \[\tfrac{4}{3} + 5\tfrac{9}{10} = \tfrac{4}{3} + \tfrac{59}{10} = \tfrac{40 + 177}{30} = \tfrac{217}{30} = 7\tfrac{7}{30}\]

(b) One number from \(\{2, 3, 4\}\) and one from \(\{1, 3, 5\}\): \(3 \times 3 = 9\) equally likely pairs.

Pairs whose sum satisfies \(3 < \text{sum} < 7\): \((2,3) = 5,\ (3,1) = 4,\ (3,3) = 6,\ (4,1) = 5\), giving 4 outcomes.

\[P = \frac{4}{9}\]

Download The App On Google Playstore

Everything you need to excel in your exams

Green Bridge CBT Mobile App
Personalized AI Learning Chat Assistant
200,000+ Exam Questions Across IGCSE, JAMB, WAEC & NECO
Over 3,900 Lesson Notes
Offline Support - Learn Anytime, Anywhere
Green Bridge Timetable
Literature Summaries & Potential Questions
Track Your Performance & Progress
In-depth Explanations for Comprehensive Learning