Question 665254
Establish variables
x = day 1
y = day 2
z = day 3
...
Given
x+y+z = 246
x=79
y = z+47
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Substitute x and y into the first equation and solve for z
...
79 + z+47 + z = 246
Combine like terms
2z = 246 - 79 - 47
2z = 120

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Divide both sides by 2
{{{highlight(z = 60)}}}people 
...
Check  {{{cartoon(
79 + (60+47) + 60,
79 + 107 + 60,
246)}}}
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