The clock face on London's Big Ben measures 23 feet across. How far does the tip of the minute hand travel between 6:50 and 7:30?

48.15 feets

Explanation:

Diameter = 23 feet (measure of clock face)

Hence, The Circumference, C of London's big ben = πd

π = 3.14

Circumference = 3.14 * 23 = 72.22 feets

Between 6:50 to 7:30 = 40 minutes

40 minutes / 60 minutes = 2 /3 of the Circumference

2/3 * Circumference

2/3 * 72.22 feets

= 48.146 feets

Distance traveled = 48.15 feets