Test on Grade 8 Mathematics Control Test

Question 1: The simplified value of the expression 7,86 + 3,7 - 4,999, rounded to two decimal places, is 6,561.

A. Ano

B. Ne

Explanation: The simplified value of the expression 7,86 + 3,7 - 4,999 is 6,561. However, when rounded to two decimal places, the value becomes 6,56, not 6,561. The question states 'rounded to two decimal places', making the original statement incorrect.

Question 2: Elvis has 7% of his pocket money left after spending on chewing gum, shoes, and a present.

A. Ano

B. Ne

Explanation: Elvis's total pocket money is R300. His expenses are R31.50 for chewing gum, R163.80 for shoes, and R84.00 for a present, totaling R279.30. This leaves R20.70 (R300 - R279.30) remaining. The percentage of pocket money left is (R20.70 / R300) x 100 = 6.9%.

Question 3: Based on the provided material's discussion of algebraic terms, which of the following pairs represents like terms?

A. 3m and 3n

B. 5y and -9y

C. 4p^2 and 4p

D. 2x and -6

Explanation: Question 8.1.1 in the study material asks to identify whether '2a and -8a' are like or unlike terms, implying that like terms share the same variable part. In the given options, '5y and -9y' both have the variable 'y' raised to the same power (1), making them like terms. The other options consist of terms with different variables, different powers of the same variable, or a variable and a constant.

Question 4: Which property of integer operations is demonstrated by the statement -5 (2 + 1) = ( - 5 X 2) + ( - 5 X 1)?

A. Commutative Property of Multiplication

B. Distributive Property of Multiplication over Addition

C. Associative Property of Addition

D. Identity Property of Multiplication

Explanation: The statement -5 (2 + 1) = ( - 5 X 2) + ( - 5 X 1) shows that multiplying a number by a sum is the same as multiplying the number by each addend and then adding the products, which is the Distributive Property of Multiplication over Addition, as seen in question 3.1 of the study materials.

Question 5: Given the formula Tn = 4n-3, if Tn is 1025, then n is 257.

A. Ano

B. Ne

Explanation: The study material shows that when Tn = 1025, the calculation is 1025 = 4n-3, which leads to 1025+3 = 4n, then 1028/4 = n, resulting in n = 257.