Question 675221
The 1st brother's head start is {{{ 60*1 = 60 }}} mi
You can start a stop watch when the 2nd brother leaves
Let {{{ d }}} = the distance the 1st brother will now travel
{{{ 200 - d }}} = the distance the 2nd brother will now travel
Let {{{ t }}} = the time it takes for them to be {{{ 260 - 60 = 200 }}}
miles apart.
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1st brother's equation:
(1) {{{ d = 60t }}}
2nd brother's equation:
(2) {{{ 200 - d = 45t }}}
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Substitute (1) into (2)
(2) {{{ 200 - 60t = 45t }}}
(2) {{{ 105t = 200 }}}
(2) {{{ t = 1.9048 }}} hrs
{{{ .9048*60 = 54.3 }}}
They will be able to talk for 1 + 1 + 54 min
or 2 hours and 54 minutes