Forecasting revenue with indices help please!

lala99

Hi all. Just going through the sample assessment on AAT site. Sample 1 task 1 part e has me stumped.
Asked to complete a sales revenue forecast for years 2-5. Given year 1 revenue actual figure of £384000.
Also given a chart with sales volume indices :
year 1 140.0; year 2 148; yr 3 152.6; yr 4 156; yr 5 160.
Second line of chart has sales price index:
Yr 1 112; yr 2 115 ; yr 3 130; yr 4 135 ; yr 5 130

Chart to complete has two rows, divided into years 1-5. Asks for sales revenue forecast for years 2-5, Top row has actual sales revenue year 1 £384000
Top row asks for forecast at year 1 prices
Bottom row asks for 'at expected process's.

Help! I have eventually hit the right answers but I don't understand how!