The range of the data: k+2, k-3, k+4, k-2, k, k-5, k+3, k-1, and k+6 is
10
11
6
8
Correct answer is B
Range = Highest value - Lowest value
= (k + 6) - (k - 5)
= 11
Find the mean of the data: 7, -3, 4, -2, 5, -9, 4, 8, -6, 12
3
4
1
2
Correct answer is D
\(Mean: \frac{7 + (-3) + 4 + (-2) + 5 + (-9) + 4 + 8 + (-6) + 12}{10} = \frac{20}{10}\)
= 2
The locus of a point P which is equidistant from two given points S and T is
the perpendicular bisector of ST
the angle bisector of PS and ST
a perpendicular to ST
a line parallel to ST
Correct answer is A
No explanation has been provided for this answer.
Find the value of a if the line 2y - ax + 4 = 0 is perpendicular to the line y + (x/4) - 7 = 0
-4
4
8
-8
Correct answer is C
2y - ax + 4 = 0 ⟹⟹ 2y = ax - 4.
y + (x/4) - 7 = 0 ⟹⟹ y = -x/4 + 7
Slope of line 1 = a/2
Slope of line 2 = -1/4
-1/4 x a/2 = -1 (product of the slope of two perpendicular lines = -1)
a/8 = 1 ⟹⟹ a = 8.
A solid hemisphere has a radius of 7 cm. Find the total surface area.
400 cm2
462 cm2
66 cm2
308 cm2
Correct answer is B
Total surface area of hemisphere = half of TSA of sphere + circumference of circle
= \(2\pi r^{2} + \pi r^{2} = 3\pi r^{2}\)
= \( 3 \times \frac{22}{7} \times 7^{2} = 462cm^{2}\)