Which of these are Arithmetic Progressions and why?
(a) 2,3,5,7,8,10,15,……..
(ii) 2,5,7,10,12,15,……..
( c) `-1,-3,-5,-7`,………

The sum of n terms of two arithmetic progressions are in the ratio (3n+8):(7n+15). Find the ratio of their 12^th terms.

The range of the following set of observations 2,3,5,9, 8, 7, 6, 5, 7, 4, 3 is

Find the mode of the following numbers : 3,5,6,7,9,12,12,7,9,3,5,6

Find mean deviation about the mean for the following data : {:("x"_(i),2,5,6,8,10,12),("f"_(i),2,8,10,7,8,5):}

A={1,2,3,4,5,6,7,8,9,10}, B={2,3,5,7}. Find A cap B

The sum of n terms of two arithmetic progressions are in the ratio (3n + 8) : (7n + 15). Find the ratio of their 12^("th") terms.

Write True or False Mean number of the numbers 5,6,7,8,9,10,11,12,13,14,15 is 10.

Tall trees of what range of height have strong buttresses at their base (a) 15 m and above (b) 5-7 m (c) 3-5 m (d) 7-10 m

Which of the following relations are functions? Give reasons. If it is a function, determine its domain and range. (i) {(2,1),(5,1),(8,1),(11,1),(14,1),(17,1)} (ii) {(2,1),(4,2),(6,3),(8,4),(10,5),(12,6),(14,7)} (iii) {(1,3),(1,5),(2,5)}

Find the mean deviation about the median for the data in {:("x"_(i),5,7,9,10,12,15),("f"_(i),8,6,2,2,2,6):}