17. On the grid below, plot and label the points with coordinates:

A(1,4), B(2,2) and C(4,3)

Write down the coordinates of a fourth point D which makes the shape ABCD a square.

26. Four friends, Alwyn, Bax, Coates and Delius have lunch together. Although each eats a differently priced snack, they share the bill equally. Yesterday, this resulted in Alwyn paying £1 less than the cost of his snack, Bax paying £3 more, Coates £4 less and Delius paid £4. What was the actual price of the snack that each friend ordered?

Alwyn: --------- Bax: -------- Coates:---------- Delius: ----------

28. In ordinary arithmetic, numbers are given in base 10 which means that for a number written as 469 there are 4 hundreds, 6 tens and 9 units so that

469 = 4 x 100 + 6 x 10 + 9 x 1

In base 5, only the digits 0, 1, 2, 3 and 4 are used. Instead of the columns representing hundreds, tens and units they now indicate how many twenty-fives, fives and units there are so the number 324 in base 5, represents 3 twenty-fives, 2 fives and 4 units so that

324 (base 5) = 3 x 25 + 2 x 5 + 4 x 1 = 75 + 10 + 4 = 89 (base 10)

Use this process to convert the numbers 13 and 341, both given in base 5, into base 10:

13 (base 5) = ------- (base 10) 341 (base 5) =--------(base 10)

The four numbers in the first column add up to 112 and the four numbers in the fourth row add up to 100.

Use this information to work out the remaining values of A, B and D.

A = ------ B= ------- D= ------