The Brandywine River is at its flood stage of 9 ft. It’s continuing to rain. The next measurement shows that the river has risen 1 1/2 ft. ft. An additional measurement shows that the river has risen 1 5/12 ft. ft. How many more feet does the river need to rise to be at the major flood stage of 13 ft.? Express your answer in simplest form.

Answer 1

The total rise of the river is 1 1/2 + 1 5/12 = <<1+5/6=13/2>>13/2 = <<13/2=6.5>>6.5 ft
The river still needs to rise 13 - 6.5 = <<13-6.5=6.5>>6.5 ft. Answer: \boxed{6.5}.