CIE Mathematics Paper-1: Specimen Questions 167 - 168 of 175

Question number: 167

Short Answer Question▾

Write in Short

The area of a square is 42.25 cm2 . Find length of one side of the square.


Here, formula for area of a square = a2 where, a is side of square.

  • So, here, a2=42.25a=42..25=6.5cm.

Question number: 168

Essay Question▾

Describe in Detail

In the diagram AC is the diameter of a circle, center O. The length of AC is 12 cm.

A circle having a triangle on half part

A circle having a triangle on half part

Find the given calculations by using the appropriate formulas of circle and triangle

(a) Write down the size of angle ABC.

(b) Angle BAC = 40°. Calculate the length of BC.

(c) Calculate the area of the circle.


Here, AC is the diameter of a circle which is of 12 cm and O is center.

(a) Size of ABC,

Here, edge AC of triangle is diameter of the circle which will be diagonal of triangle ABC.

So, we can see in the figure, it is a right angled triangle, so ABC=900.

  • The triangle formed by the diameter and the inscribed angle (triangle ABC above) is always a right triangle.

(b) Here, Angle BAC = 40° and length of AC is 12 cm.

So, using cosine formula of triangle:


(C) Area of circle = 2πr2 , where r = radius of circle.

So, here diameter AC = 12 cm, so radius = diameter2=122=6cm .

So, area of circle = 2πr2=2×3.14×62=2×3.14×36=226.08cm2 .