Luisa travels 25 km in 3hours 45 mins. She walks part of the way at 4 km/h and cycles the rest at 12 km/h. How far did she walk?

Answer 1

walked for t hours

times are t and 3.75-t

4 t + 12(3.75-t) = 25

-8 t = 25 - 45 = -20

t = 5/2

d = 4 (5/2) = 10 km

Answer 2

good