√27cm
312cm
7cm
7√2cm
Correct answer is D
A=\pi r^2 \Rightarrow 77 = \frac{22}{7} \times \frac{r^2}{1}\Rightarrow r^2 = \frac{77\times 7}{22} \Rightarrow r^2 = \frac{49}{2}\\ \Rightarrow r = \sqrt{\frac{49}{2}}=\frac{7}{\sqrt{2}}. Since D = 2r ∴ D = 2 \times \frac{7}{\sqrt{2}} = \frac{14}{\sqrt{2}} \times \frac{\sqrt{2}}{\sqrt{2}} = 7\sqrt{2}cm
If cos θ = 5/13, what is the value of tan \theta for 0 < θ < 90°...
If O is the centre of the circle in the figure, find the value of x ...
In how many ways can the letter of ZOOLOGY be arranged? ...
The subtraction below is in base seven. Find the missing number. 5 1 6 2seven -2 6 4 4seven -----...
In the diagram above, |PQ| = |QR|, |PS| = |RS|, ∠PSR = 30o and ∠PQR = 80o. Find ∠SPQ....
Find the equation whose roots are -2/3 and -1/4 ...
If dy/dx = 2x - 3 and y = 3 when x = 0, find y in terms of x. ...
Write as a single fraction \frac{1}{1 - x} + \frac{2}{1 + x}...