Question 723684
Think of this as one train standing still and the
other moving at the sum of their speeds.
Let {{{ t }}} = the time in hours for them to meet
{{{ 456 = ( 100 + 90 )*t }}}
{{{ t = 456 / 190 }}}
{{{ t = 2.4 }}}
They will meet in 2.4 hrs
check:
Faster train:
{{{ d[1] = 100*2.4 }}}
{{{ d[1] = 240 }}} mi
and
Slower train:
{{{ d[2] = 90*2.4 }}}
{{{ d[2] = 216 }}} mi
----------------
{{{ d[1] + d[2] = 240 + 216 }}}
{{{ d[1] + d[2] = 456 }}}
OK