| Solving Mr Kenwright's Problems |
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| If you like, you can record your answers and bring them into school. |
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1 Odd Operations |
In class, I gave you a Theory (an idea to test):
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| This is my Theory, it is mine: |
| odd whole numbers X even numbers = even numbers |
| even X even = even |
| odd X odd = odd |
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| No-one has given me a sum that breaks these rules. Can you? |
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| Stephen thought of a Theory: |
| odd + even = odd |
| even + even = even |
| odd + odd = even |
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| Can you find sums that fit his theory? Can you find any that don't fit? |
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| Challenge: |
| Can you come up with a similar theory for subtraction (take away)? |
| - beware, it works a little differently |
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| Can you come up with a similar theory for division? |
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| Can you prove they are right? |
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2 Dice Combinations |
| If you throw a pair of dice, you could get totals as low as (1 + 1 =) 2 or as large as (6 + 6 = ) 12. If you throw a pair of dice twenty times, you could get totals as low as (20 X 2 =) 40 or as large as (20 X 12 = ) 240. But when we did it in class, each group got between 116 and 155. Why? |
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| Here are the possible throws: |
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| If it worked like times tables, you could get 21 combinations, but each die is different (try it with different coloured dice). |
We investigated and found that:
There is only one way to score two (1 and 1) and one way to score twelve (6 and 6). There are two ways to score three: (2 and 1) and (1 and 2).
There are two ways to make the three and eleven.
There are three ways to make the four and ten.
There are four ways to make the five and nine.
There are five ways to make the six and eight.
There are six ways to make the seven. |
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| Here is another way to look at it: |
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or: or: |
| So how many possible throws are there really and what chance do you have of throwing a 7? |
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| 3 Time Flies |
You start with a fly in a jar and the next day have two. Each day the number doubles. How many will you have in a week?Two weeks?
After a month? |
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