Question 464969
You can think of this as one plane being stationary
and the other one flying towards it at the sum of their speeds
If one plane's speed is {{{s}}}, the other is {{{ s + 75 }}}
The plane that is moving has to fly {{{ 2475 }}} mi
{{{ 2475 = (s + s + 75)*3 }}}
{{{ 2475 = 6s + 225 }}}
{{{ 6s = 2250 }}}
{{{ s = 375 }}}
{{{ s + 75 = 450 }}}
The speeds of the planes are 375 mi/hr and 450 mi/hr
To check answers:
How far does slower plane go in 3 hrs?
{{{ d[1] = 375*3 }}}
How far does faster plane go in 3 hrs?
{{{ d[2] = 450*3 }}}
Does {{{ d[1] + d[2] = 2475 }}} ?
You can check