Nancy is driving and makes a wrong turn. The satnav indicates that her journey will take an extra 7 minutes. Nancy drives at an average speed of 60km/h to the nearest 5km/h. What's the greatest possible distance traveled in this detour in km to 2.d.p?

Start by selecting useful information in the text.time = 7 minutesspeed = 60km/h to the nearest 5km/hmaximum possible distance travelled = ? kmWe know a time and speed and want to know a distance. So we can use the equation:speed = distance / time or v = d / tWhich can be rearranged for distance as: d = v t (use of a equation triangle)We are after the maximum possible distance. Speed is:v = 60km/h to the nearest 5km/hFor the maximum distance travelled the speed is the slowest possible (imagine a tractor and a lamborghini in race). The slowest possible speed is 55km/h as the speed is to the nearest 5km/h.We need to check all units work with each other. Time is in minutes and speed is in km/h. Therefore the units of time need to be converted.There are 60 minutes in 1 hour so 7 minutes is 7/ 60 x 1 hour.t = 7/60 hours.Finally use the equation:d = v t d = 55 x (7/60) d = 6.41666 kmans to two decimal places therefore:d = 6.42 km