Systematic listing
The Maths Habit
Amy, Ben and Cal stand in a line. Sam lists every order. Is his list right?
CBA is missing.
Keep the first card. Swap the other two.
- List
- Things written down one under another.
- Systematic
- In a fixed order, so nothing is missed and nothing is written twice.
- 1Fix the first one.Write each main once for every side.
- 2Change the rest in order.Go through the sides in order.
- 3Count them.Count the meals.
A meal is one main and one side. List all the meals.
A snack is one drink and one fruit. List all the snacks.
A meal is one main and one side. List all the meals.
A pizza is one base and one topping. List all the pizzas.
A meal is one main and one side. List all the meals.
A lunch is one roll and one drink. List all the lunches.
A meal is one main and one side. List all the meals.
An ice cream is one flavour and one topping. List all the ice creams.
1A breakfast is one cereal and one drink. List all the breakfasts.
2A meal is one main and one side. List all the meals.
3A dessert is one cake and one topping. List all the desserts.
- 1Fix the first one.Each card has a turn first. Write it twice.
- 2Change the rest in order.The other two cards can go two ways.
- 3Count them.Count the numbers.
List all the 3 digit numbers. Use each card once.
List all the 3 digit numbers. Use each card once.
List all the 3 digit numbers. Use each card once.
List all the 3 digit numbers. Use each card once.
List all the 3 digit numbers. Use each card once.
List all the ways to put the cards in a row.
List all the 3 digit numbers. Use each card once.
List all the 3 digit numbers. Use each card once.
Answer sheet
Is it right?
Thumbs up: right. Thumbs down: wrong.
3 cards make 6 numbers.
Right2 mains and 2 sides make 4 meals.
Right3 mains and 2 sides make 5 meals.
Wrong: there are 6The biggest number from 4, 5 and 6 is 654.
Right
A café has 4 mains and 3 puddings. How many meals of one main and one pudding? Do not list them.
4 × 3 = 12Cards show 0, 4 and 7. A number cannot start with 0. List all the 3 digit numbers.
407, 470, 704, 740Two of Ali (A), Bo (B), Cy (C) and Di (D) are picked for a team. List all the pairs.
AB, AC, AD, BC, BD, CD
A meal is a main and a side. Mains: pie (P), wrap (W). Sides: salad (S), beans (B). List all the meals.
PS, PB, WS, WBThree cards show 3, 7 and 8. List all the 3 digit numbers. Use each card once.
378, 387, 738, 783, 837, 873Dan (D), Eve (E) and Fay (F) sit in a row. List all the orders.
DEF, DFE, EDF, EFD, FDE, FED