11. Bill climbs a 2-mile hill at an uphill speed of 2 MPH, spends no to at the
top, and immediately walks down at 6 MPH. What is his average speed for the up and down trip?

3 MPH. 1 hour up, 20 minutes down = 80 minutes for 4 miles; 20 minutes per mile, 3 MPH.

12. What are A and B in this mathematical expression?

79 = 15 x B^{A} + A x 2^{A}

A = 4; B = 1. 79 = 15 x 1 to the 4th power + 4 x 2 to the 4th power.

13. The combined ages of Mark and Andrew are 44, and Mark is twice as old as
Andrew was when Mark was half as old as Andrew will be when Andrew is three times as old as Mark was when Mark was three times as old as Andrew. How
old is Mark? If you cannot work it out, ask your friends to help you, and watch the bewilderment creep over their faces as they attempt to grapple with
the problem.

Mark is 27 and 1/2 and Andrew is 16 and 1/2.

14. Can you solve the following sequence?

11, 12, 26, 81, 82, 166, 501, 502, ?

1006. The sequence is to multiply by 1 & then add 1, multiply by 2 & then add 2, multiply by 3 & add 3, multiply by 1 & add 1, multiply by 2 & add 2, multiply by 3 & add 3, etc.

15. Mrs. Murphy wanted some oranges, so she sent Margaret to the corner shop to
get them. Margaret came back a few minutes later with some oranges and six lollipops, having spent a total of 43 cents. Unfortunately, she didn't buy
enough oranges, so her brother Mike was sent to get some more. He returned soon after, also with some oranges and seven sticks of toffee, having spent the
same amount as his sister. What are the prices of the oranges, the lollipops, and the toffee sticks? Each of the items costs a whole number of cents, and all the items are realistically priced.

Despite the number of missing prices, the solution can be found if you consider in turn the different numbers of lollipops and toffee sticks that might have been bought, looking for the common factor in the amounts of money left each time, which will be the price of the oranges. As the prices are realistic, a common factor of 1 is excluded. And the prices turn out to be 5 cents for an orange, 3 cents for a lollipop, and 4 cents for a toffee stick.

16. What is the four-digit number in which the first digit is one-fourth of the
last digit, the second digit is 6 times the first digit, and the third digit is the second digit plus 3?

17. If 3 salesmen can sell three stoves in seven minutes, how many stoves can six salesmen sell in seventy minutes?

Six salesmen can sell 60 stoves in seventy minutes.

18. What number comes next in the sequence?

1, 6, 13, 22, 33, ?

46. Starting with the integer 2, square each consecutive integer, then subtract 3.

19. Molly is buying some new fishing equipment at a sporting goods
store where there is a sale. Everything in the store is 25% off, and cash purchases receive another 25% off the sale price. What
will Molly pay in cash for fishing equipment with a pre-sale price of $100?

$56.25. Not $50. It works like this: 25% off $100 is $75. Now the second 25% is taken off the sales price; so 25% of $75 is $18.75. Subtract that from $75 and you get $56.25.

20. Find the number that best
fits into the following sequence.

60 60 24 7 __ 10

52. There are 60 seconds in a minute, 60 minutes in an hour, 24 hours in a day, 7 days in a week, 52 weeks in a year and 10 years in a decade.