Egyptian Temperatures
The sum of a quantity, half the quantity, a fifth of the quantity, a tenth of the quantity, and 32 is 57 and a fifth. What is the quantity?
Egyptian way:
First, simplify (very important)
x + x/2 + x/5 + x/10 + 32 = 57 + 1/5
x + x/2 + x/5 + x/10 = 25 + 1/5
Try x = 5 (False Position)
5 + 5/2 + 5/5 + 5/10
= 5 + 2 + 1/2 + 1 + 1/2 = 9
= 5 + 2 + 1/2 + 1 + 1/2 = 9
Have 9, want 25 + 1/5, so divide 5 by 9, multiply by 25 + 1/5:
5/9 * (25 + 1/5)
x = (1/2 + 1/18) * (25 + 1/5)
= 25/2 + 1/10 + 25/18 + 1/90
= 12 + 1/2 + 1/10 + 1 + 7/18 + 1/90
= 12 + 1/2 + 1/10 + 1 + 1/3 + 1/18 + 1/90
= 14
Check: x = 14
14 + 14/2 + 14/5 + 14/10 + 32
= 14 + 7 + 2 + 4/5 + 1 + 2/5 + 32
= 57 + 1/5
Modern way:
x + x/2 + x/5 + x/10 + 32 = 57 1/5
x + x/2 + x/5 + x/10 + 32 = 57 1/5
9x/5 + 32 = 57 1/5
9x/5 = 25 1/5
x = 14
Very interesting!
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