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when the diameter of a circle is trebled , the area is multiplied by how many times?

when the diameter of a circle is trebled , the area is multiplied by how many times? Correct Answer 9

ব্যাসার্ধ r হলে ব্যাস 2r এবং ক্ষেত্রফল πr2 ব্যাস 2r এর তিনগুণ = (2r × 3) = 6r যখন ব্যাসার্ধ 3r ⸫ ক্ষেত্রফল = a(3r)2 = 9 πra2 অর্থাৎ, ক্ষেত্রফল প্রথমটির 9 গুণ।

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Simplify the value of $$\frac{{{\text{0}}{\text{.9}} \times {\text{0}}{\text{.9}} \times {\text{0}}{\text{.9 + 0}}{\text{.2}} \times {\text{0}}{\text{.2}} \times {\text{0}}{\text{.2 + 0}}{\text{.3}} \times {\text{0}}{\text{.3}} \times {\text{0}}{\text{.3}} - {\text{3}} \times 0.9 \times {\text{0}}{\text{.2}} \times {\text{0}}{\text{.3}}}}{{{\text{0}}{\text{.9}} \times {\text{0}}{\text{.9 + 0}}{\text{.2}} \times {\text{0}}{\text{.2 + 0}}{\text{.3}} \times {\text{0}}{\text{.3}} - 0.9 \times {\text{0}}{\text{.2}} - {\text{0}}{\text{.2}} \times {\text{0}}{\text{.3}} - 0.3 \times 0.9}} = ?$$
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When the diameter of a circle is trebled , the area is multiplied by how many times ?
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$$\eqalign{ & {\text{The}}\,{\text{value}}\,{\text{of}} \cr & \frac{{0.1 \times 0.1 \times 0.1 + 0.02 \times 0.02 \times 0.02}}{{0.2 \times 0.2 \times 0.2 + 0.04 \times 0.04 \times 0.04}}\,\text{is}: \cr} $$
The value of $$\left( {\frac{{0.1 \times 0.1 \times 0.1 + 0.02 \times 0.02 \times 0.02}}{{0.2 \times 0.2 \times 0.2 + 0.04 \times 0.04 \times 0.04}}} \right)$$       is :