Here's how I solved it:

1) RetailCo's RMS for each state is mentioned directly below the chart, so you shouldn't need to calculate this for each state.

Note: in case you do want to calculate its RMS in each state, just for practice, it is their market share in that state divided by the market share of the single competitor with the largest market share in that state. If Retail Co has the largest market share, then look at the next biggest single competitor and use that competitor's market share for the denominator.

2) Total sales by all players in each state is mentioned directly above the chart.

3) To calculate RetailCo's RMS across the four states, you will have to take their weighted average RMS across the four states. One way you can do this is as follows:

a) Take the sum of the following:

(RetailCo RMS in State 1 * Total Rev of all players in State 1) + (RetailCo RMS in State 2 * Total Rev of all players in State 2) + (RetailCo RMS in State 3 * Total Rev of all players in State 3) + (RetailCo RMS in State 4 * Total Rev of all players in State 4)

b) Divide that sum by the total Revenue of all players across the four states

So, it would be as follows: ((2.1*2.3)+(0.8*1.70)+(0.9*1.4)+(.6*1))/(6.40)

This would equal approximately 1.2

(edited)

I got a similar question. Could you actually calculate this out and show how you come to the answer? I just did a straight weighted average of sales and that also equals 1.2 so I'm not sure how the formula works...