NBT Logical Reasoning & Problem Solving 2

Question 1

All students in the maths class passed the exam. Thabo is a student in the maths class. What must be true?

Accepted Answer

Thabo passed the exam

Answer

This is a valid deductive argument (syllogism). If all students passed and Thabo is a student in the class, then Thabo must have passed.

Question 2

A pattern of numbers: 3, 6, 12, 24, ___. What is the next number?

Accepted Answer

48

Answer

Each term is multiplied by 2. 24 × 2 = 48.

Question 3

Siya is taller than Bongani. Bongani is taller than Lungile. Which of the following must be true?

Accepted Answer

Siya is taller than Lungile

Answer

If Siya > Bongani and Bongani > Lungile, then by transitivity: Siya > Lungile.

Question 4

If "all mammals breathe air" and "dolphins are mammals," what is the logical conclusion?

Accepted Answer

Dolphins breathe air

Answer

Valid deductive reasoning: dolphins are mammals (given), all mammals breathe air (given), therefore dolphins breathe air.

Question 5

A student must choose 2 subjects from: Mathematics, History, Science, and Art. How many different combinations are possible?

Accepted Answer

6

Answer

Combinations: C(4,2) = 4! / (2! × 2!) = (4 × 3) / (2 × 1) = 6 combinations.

(NBT) National Benchmark Test Practice Test