1.Correct Answer: C
Explanation:
Sketch a diagram and calculate the distance (hypotenuse of a right triangle) using
Pythagoras theorem.
Vertical height of triangle = 5 ; horizontal side = 4 ; hypotenuse = √(25 + 16) = √41☆7.Correct Answer: A
Explanation:
Each of the integers in the first set could be combined with any from the second set, giving a total of 4 x 5 = 20 possible pairs.
Of these the combinations that could give a sum of 23 are (5 + 18), and (9 + 14)
This means that the probability of getting a sum of 23 is 2/20 = 1/10
☆8.Correct Answer: C
Explanation:
If the price is reduced by 15 %, then the new price will be 0.85D
If this new price is further reduced by 10%, the discounted price will be 0.9 x 0.85D = 0.765D
☆9.Correct Answer: E
Explanation:
The longest line segment that can be drawn without passing through any dots other than those at the beginning and end of the segment, such a line could go from the middle dot in the top row to either the bottom left or right dot. In any case the segment will be the hypotenuse of a right triangle with sides 2 and 4. Using Pythagoras theorem the hypotenuse will be √(2 2 + 4 2 ) = √20
☆10.Correct Answer: D
Explanation:
If the radius is 7, the circumference = 14π
The length of the arc is 100/360 of the circumference
Taking π as 22/7 we get
(100 x 14 x 22) / (360 x 7) which reduces to 440/ 36 = 12.22 (i.e. approx. 12)