Question 1058889
Let {{{ 1/t }}} Camden's rate of working in the units:
[ 1 van repaired ] / [ t hrs ]
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{{{ 1 / (25/3) = 3/25 }}} = Aiden's rate of working
[ 3 vans repaired ] / [ 25 hrs ] which is the same as:
[ 1 van repaired ] / [ 8.333 hrs ]
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Together, their rate is:
{{{ 1/5 }}} = 
[ 1 van repaired ] / [ 5 hrs ]
Add their rates of working to get
their rate working together
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{{{ 3/25 + 1/t = 1/5 }}}
Multiply both sides by {{{ 25t }}}
{{{ 3t + 25 = 5t }}}
{{{ 2t = 25 }}}
{{{ t = 12.5 }}}
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Working alone, Camden can fix the van
in 12.5 hrs
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check:
{{{ 1/8.333 + 1/12.5 = 1/5 }}}
{{{ .12 + .08 = .2 }}}
{{{ .2 = .2 }}}
OK