The numbers are written in five columns to make a pattern.
| |
Column
1 |
Column
2 |
Column
3 |
Column
4 |
Column
5 |
Column
6 |
| Row 1 |
14 |
15 |
16 |
17 |
18 |
19 |
| Row 2 |
20 |
21 |
22 |
23 |
24 |
25 |
| Row 3 |
26 |
27 |
28 |
29 |
30 |
31 |
| Row 4 |
32 |
33 |
34 |
35 |
36 |
37 |
.
.
. |
|
|
|
|
|
|
| Row x |
f |
|
A |
|
|
|
| Row (x + 1) |
|
B |
C |
|
|
|
- Find A in terms of f.
- Find B in terms of f.
- Find C in terms of f.
- Express f in terms of x.
(a)
A = f + 2
(b)
The number to the right of f = f + 1
Pattern for Column 2
Row 1 Column 2: 9 + 6 x 1 = 15
Row 2 Column 2: 9 + 6 x 2 = 21
Row 3 Column 2: 9 + 6 x 3 = 27
Therefore each consecutive row differs by 6.
B = f + 1 + 6 = f + 7
(c)
C = f + 7 + 1 = f + 8
(d)
Pattern for Column 1
Row 1 Column 3: 8 + 6 x 1 = 14
Row 2 Column 3: 8 + 6 x 2 = 20
Row 3 Column 3: 8 + 6 x 3 = 26
Formula:
Number = 10 + 6 x Row number
Let x be the row number
A = 10 + 6 x
f = 10 + 6 x - 2 = 8 + 6 x
Answer(s): (a) f + 2 or 2 + f ; (b) f + 7 or 7 + f ; (c) 7 + f or f + 7 ; (d) 6x + 8 or 8 + 6x or 6 x + 8 or 8 + 6 x
