range, mean, median and mode

(a)

The following set of data refers to the global sales in £1000s taken from a new mobile phone product in 6 consecutive months.

[Oct 350.90, Nov 340.70, Dec 440.40, Jan 280.92, Feb 490.60, Mar 290.68]

Determine the range, mean, median and mode values for the set.

(b)

The frequency distribution for the value of resistance in ohms of 68 resistors is as shown. Determine the mean, median and mode value of resistance.

20.5-20.9 8, 21.0-21.4 20,

21.5-21.9 13, 22.0-22.4 13,

22.5-22.9 9, 23.0-23.4 5