Determine the estimated mean of the following frequency distribution.

Class Frequency

20 up to 30 7

30 up to 40 12

40 up to 50 21

50 up to 60 18

60 up to 70 12

A sample of the amounts paid for parking on Saturday at the Downtown Parking Garage in Toronto was organized into the following frequency distribution.

Amount Paid Frequency

$0.50 up to $0.75 2

0.75 up to 1.00 7

1.00 up to 1.25 15

1.25 up to 1.50 28

1.50 up to 1.75 14

1.75 up to 2.00 9

2.00 up to 2.25 3

2.25 up to 2.50 2