12.4 years
12.6 years
13.2 years
14.1 years
Correct answer is B
\(Mean = \frac{\text{sum of ages}}{\text{no of pupils}}\)
Let the sum of the ages of the 15 pupils be x and the sum of the 16 pupils be y.
\(\frac{x}{15} = 14.2 \implies x = 14.2 \times 15 = 213\)
\(\frac{y}{16} = 14.1 \implies y = 14.1 \times 16 = 225.6\)
\(\text{Age of new pupil} = 225.6 - 213 = 12.6\)
Which of the following is an item of prime cost?
Royalities payable
Factory salaries
Depreciation of plant
Rent of factory building
Correct answer is A
No explanation has been provided for this answer.
Find the equation of the tangent to the curve \(y = 4x^{2} - 12x + 7\) at point (2, -1).
y + 4x - 9 = 0
y - 4x - 9 = 0
y - 4x + 9 = 0
y + 4x + 9 = 0
Correct answer is C
\(y = 4x^{2} - 12x + 7\)
\(\frac{\mathrm d y}{\mathrm d x} = 8x - 12\)
At x = 2, y = 8(2) - 12 = 4
Equation of the tangent to the curve: \(y - (-1) = 4(x - 2)\)
\(y + 1 = 4x - 8 \implies y - 4x + 1 + 8 = y - 4x + 9 = 0\)
Find the axis of symmetry of the curve \(y = x^{2} - 4x - 12\).
x = -2
y = -2
x = 2
y = 2
Correct answer is C
The vertical line \(x = \frac{-b}{2a}\) is the axis of symmetry of the curve.
\(y = x^{2} - 4x - 12\)
\(\text{Axis of symmetry} = x = \frac{-(-4)}{2(1)} = \frac{4}{2} = 2\)
₦262,000
₦224,000
₦221,000
₦176,000
Correct answer is C
No explanation has been provided for this answer.