ABCDEFGHIJKLMNOPQRSTUVWXYZ
1
If a number S is the square root of N, then SxS=N.
2
So N/S=S.
3
4
How this method works to find the square root of a number N:
5
Make a guess, G.
6
Check whether it is right by dividing N/G.
7
If this equals G, you're done.
8
If not, then G will be too small and N/G too big, or vice versa.
9
The square root of N is in between these two.
10
Average G and N/G to get your next guess.
11
Repeat until G and N/G are close enough for the amount of accuracy you need.
12
13
Try it! Change ONLY the numbers in shaded cells, C15 and A18:
14
15
Find the square root of this number, N:
7
16
17
GuessCheck: N/Guess
18
32.333333333
19
2.6666666672.625
20
2.6458333332.645669291
21
2.6457513122.64575131
22
2.6457513112.645751311
23
2.6457513112.645751311
24
2.6457513112.645751311
25
2.6457513112.645751311
26
2.6457513112.645751311
27
2.6457513112.645751311
28
2.6457513112.645751311
29
2.6457513112.645751311
30
2.6457513112.645751311
31
2.6457513112.645751311
32
2.6457513112.645751311
33
2.6457513112.645751311
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100