Subject
Quantitative Aptitude
Topic
Circles
The radius of a circle is increased by 10%, then the area is increased by what percent?
The radius of a circle is increased by 10%, then the area is increased by what percent?
ক)
10%খ)
20%গ)
21%ঘ)
100%Explanation
Area of circle A = π*r2 Increase r by 10% new area is: π*(1.1r)2 = 1.21*π*r2 thus area is increased by (1 - 1.21) = 0.21 = (0.21*100)% = 21%Related questions
How many times in a day, the hands of a clock are straight?বৃত্তের ব্যাস তিনগুণ বৃদ্ধি করলে ক্ষেত্রফল কতগুণ বৃদ্ধি পাবে?Between the two chords AB and CD of a circle, AB is closer to the centre. Which of the following propositions is correct?What is the radius of the in-circle of the triangle whose sides measure 5, 12 and 13 units?If the area of a circle is 81π, then the circumference of the circle is:OA and OB are two tangents drawn in circle ABC from exterior angle O. Therefore-What is the volume of a cube whose surface area is 96?The side length of a square inscribed in a circle is What is the area of the circle shown at the right?