Prime Number, Square Number, Sequence

Here are 5 rows of numbers.

 

Row A

2

4

6

8

10

12

14

16

 

 

Row B

3

5

7

9

11

13

15

17

 

 

Row C

2

3

5

7

11

13

17

 

 

 

Row D

1

2

5

10

20

50

100

200

 

 

Row E

1

2

4

8

16

32

64

 

 

 

All the numbers are even in one of the rows.

 

(a)   Which row?

 

……………

 

(1)

 

(b)   The numbers in Row C are the first 7 prime numbers written in order of sizes.

 

 

 

Write the next prime number.

 

……………

(1)

 

(c)   Write down a square number from Row D.

 

 

 

……………

 

(1)

 

The numbers in Row E are the first 7 numbers of a sequence.

 

 

 

(d)   Work out the next number in the sequence.

 

……………

 

(1)

 

(Total 4 marks)

Answers

 

(a) Row A

(b) 19

(c) 100 (can also be 1)

(d) 128 ( each number doubles, nth term =  2n)

 

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Students note:

- knowing your square numbers (say the first 10) will help with finding answers to square roots, e.g. square root of 100 is 10

 

- there are two ways of finding nth term in a sequence: finding the right pattern and or working our the rule.

 

Teachers note:

It can be helpful to use the same test format when setting test

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