It will cost a total of £530 to hire from the cheaper company, which is company A.
How much will it cost to hire a car from each company?
To compare the price offered by each company we need to calculate the price for each company as follows:
Company A: £20 per day and 50p per mile
£20 x 7 days= £140
50 p x 750 = £375
Total: £515
Company B: £40 per day and 30p per mile
£40 x 7 days= £280
30 p x 750 = £250
Total: £530
Based on this, company A is cheaper than company B, and it will cost a total of £530 to rent a car in that company.