(i) The following table gives the marks scored by a set of students in an examination. Calculate the mean of the distribution by using the short cut method.



(ii) What number must be added to each of the numbers 4, 6, 8, 11 in order to get the four numbers in proportion?

(iii) Using ruler and compass construct a triangle ABC in which AB = 6 cm, ∠BAC =120° and AC = 5 cm. Construct a circle passing through A, B and C. Measure and write down the radius of the circle.

Solution

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