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Multiplication Lives. Cuneiform tablet found in West Asia about 2700 BC The table helps people figure out the area of a region by multiplying width by length. The first column is the width, the second is the length, and the third column is the area.
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Multiplication Lives
Cuneiform tablet found in West Asia about 2700 BC • The table helps people figure out the area of a region by multiplying width by length. • The first column is the width, the second is the length, and the third column is the area. • It uses a system for writing down large numbers in base 60 (the way our clocks work today).
Let’s analyze what’s happening. Simplest type problem: = 6 2 x 3
= 20 4 x 5
10 lines 10 points + What about a problem like this? 13 x 4 = 52 The intersection of 13 lines 4 lines. 12 4
Sample Problem: 12 x 234
100 12 x 234 (2 x 2) 100 10 (1 x 2) 1000 (2 x 3) 10 10 7 8 2 1 (1 x 3) 100 (2 x 4) 1 2808 (1 x 4) 10 1 10
100 10 1 1 10 100 a b c x d e f c 100 b 1000 10 a 10000 100 1 d 1000 10 e 100 f
a b c d e f x a bc x def cf ad ae+bd af+be+cd bf+ce 100 10 1 10,000 1,000
a b c d e f x + a bc x def cf ad ae+bd af+be+cd bf+ce 100 10 1 10,000 1,000 fa af fb bf fc cf ea ae eb be ec ce da ad db bd dc cd
10? 10? 10? 10? 10? 10? a.bc x de.f c b a d e f
101 100 10-1 10-2 10-1 100 a.bc x de.f c b a d e f