We are given first day amount=$3,000,000.
According to given problem, that amount double that amount the next day.
But please note the double amount is added to the amount present initially.
So, each time we will add $3,000,000 to the double amount to get the final amount for a particular day.
For second day amount will be 3,000,000+ double of 3,000,000, that is = 3,000,000 + 6,000,000 = $9,000,000.
Third day amount = 3,000,000 + 2*9,000,000 = $21,000,000.
Fourth day amount = 3,000,000 + 2*21,000,000 = $45,000,000.
Fifth day amount = 3,000,000 +2*45,000,000 = $93,000,000.
Sixth day amount = 3,000,000 +2*93,000,000 = $189,000,000 .