Calculate how much gasoline and money could be saved if the automobile's fuel efficiency were increased by 25%.

Gasoline = 25 gallons per week

Money = $2 per gallon ($50 total)

In the question it is already given the amount of actual gasoline and money consumed before the fuel efficiency gets increased by 25%

Gasoline consumption before the increase in fuel efficiency = 25 gallons per week

Gasoline saved after the increase in fuel efficiency = [25 * (25/100) ] gallons per week

= 6.25 gallons per week

So every week 6.25 gallons of gasoline can be saved after increasing the efficiency of the automobile by 25%.

Then

The amount of money saved against the 6.25 gallons of gasoline saved = (6.25 * 2) dollars

= 12.50 dollars

The amount of money saved is $12.50 per week.