Prime+numbers,+Factors,+HCF+&+LCMs

and
 * 1. Prime Number Puzzles**
 * Two different prime numbers, each less than 100, are multiplied.
 * the answer ends in 2
 * What could the numbers be?
 * Two 2-digit prime numbers are multiplied.
 * The answer is 4717
 * Which two prime numbers were multiplied?


 * 2. What is a prime factor?**


 * 3. Using tables or factor trees to write numbers as products of prime factors**
 * Teacher examples for 88, 396 & 4680
 * Using the white boards and working with your partner, complete 2,a,b & c
 * Again using the white boards, use tables or factor trees to help you write 5 f, g, h, & i as products of prime numbers
 * Complete Review 1-3 in your books


 * 4. Puzzle**
 * There are just four numbers less than 100, with exactly three factors.
 * One of these is 9. What are the other three?
 * 5. Highest common factor and lowest common multiple**


 * 6. On the white boards...**
 * Complete 1 a then hold it up so I can see it
 * Do the same for 1 b, c & d
 * Now complete all of 2 & 3 on the white boards\


 * 7. Into your books - title (Highest Common Factors and Lowest Common Multiples), date...**
 * Complete questions 4, 5, 6 & 7.
 * Extension1: Review 3.


 * 8. Puzzle time!**
 * Jack thinks of a number. He works out all except two of the numbers from 1 up to 10 are factors of this number.
 * The two numbers that are not factors are consecutive.
 * What is the smallest number Jack could be thinking of?


 * 9. Extra challenge**
 * If you finish Questions 4,5,6 & 7, as well as Review 3 have a go at these from the Year 9 book...

//Cancel these fractions by finding the HCF of the numerator and the denominator.// a. 154/330 b. 525/2310 c. 1980/4752

//Add or subtract these fractions by finding the LCM of the denominators//: a. 7/45 + 9/72 b. 29/180 - 37/240 c. 11/280 + 53/392