Please let me how to solve the question in the attached image to arrive at the ans marked in the squares of each column
IRQ2  How to solve
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If they ask for an approximate value, we can just ballpark our answers! We can safely take Ï€ to be 3 so that 4Ï€r^2 is 12r^2. Rate is $92 per square meter, close to 90, so the cost is close to 12r^2 times 90, which is 1080r^2.
A 5.50 meter circumference means the radius is 5.5/ (2 Ï€), slightly less than 1 and so is r^2. Therefore, 1080r^2 would be around $1000 or less, pick A.
A 7.85 meter circumference means the radius is 7.85/ (2 Ï€), around 1.3 and so r^2 is around 1.7. Therefore, 1080r^2 would be something near to 2000 and less. Pick C
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Sanjeev K Saxena
Quantitative Instructor
The Princeton Review  Manya Abroad
Lucknow226001
www.manyagroup.com