Question 1007980
How much does a fish weigh if its tail weighs 5kg, its head weighs half as much as the tail and body together, and the body weighs as much as the head and tail altogether? 
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Equations:
t = 5
h = (1/2)(t+b)
b = h + t
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Substitute to simplify::
t = 5
2h = 5 + b
b = h + 5
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Sustitute for "b" and solve for "h"::
2h = 5 + h+5
h = 10 (wt. of head)
t = 5 (wt. of tail
b = h+5 = 15 (wt of body)
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Ans:: fish weighs 5 + 10 + 15 = 30 kg
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Cheers,
Stan H.
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