2. 6 ways
(1X 20c + 1 X 10c)
(1 X 20c + 2 X 5c)
(3 X 10c)
(2 x 10c + 2 X 5c)
(1X10c + 4 X 5c)
(6 X 5c)
3. (a) 7m X 5 m (b) 35 square metres
5. Mother 73, daughter 37
When Leo says “I lie on both Mondays and Tuesdays” then says “I lie on both Wednesdays and Fridays”:
Both those statements can’t be true because he only tells the truth once in the week.
Both those statements can’t be false, because if they were it would mean he would be tells the truth at least twice in one week.
So ONE of those statements is true, and one is false.
So Leo tells the truth one of these four days; Monday, Tuesday, Wednesday or Friday.
On the day that Leo says “Today is either Thursday, Saturday or Sunday”, that has to be a lie. That statement was made on Monday, Tuesday, Wednesday or Friday.
If it was made on a Monday, then Leo said “I lie on both Mondays and Tuesdays” on Sunday, and “I lie on both Wednesdays and Fridays” on a Tuesday.
If it was made on a Tuesday, then Leo said “I lie on both Mondays and Tuesdays” on Monday, and “I lie on both Wednesdays and Fridays” on a Wednesday.
7. The letter A
8. a. Thirty cubes b. forty cubes
9. a. 1st Duncan, 2nd Billy, 3rd Adrian b. Duncan, Billy, Adrian, Keith
10. 11 cartons: 7 of large boxes (7 x 8 = 56 boxes) 4 of small boxes (4 x 10 = 40 boxes)