<PRE><B>Question 1065649</B>
use rate * time = distance
:
r(1) * t(1) + r(2) * t(2) = 63
:
12 minutes = 12 / 60 = 1 / 5 = 0.2 hour
:
we are given r(1) = r(2) = 45, t(1) = t + 0.2 and t(2) = t
:
45(t + 0.2) + 45t = 63
:
45t + 9 + 45t = 63
:
90t = 54
:
t = 54 / 90 = 6 / 10 = 0.6
:
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family one drove 0.8 hour or 48 minutes
:
family two drove 0.6 hour or 36 minutes  
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