Question 1028965
Let {{{ s }}} = the speed of the slower boy
{{{ s + 1 }}} = the speed of the faster boy
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You can think of this as one of them standing still
and the other moving at the sum of their speeds
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{{{ 7 = ( s + s + 1 )*1 }}}
{{{ 7 = 2s + 1 }}}
{{{ 2s = 6 }}}
{{{ s = 3 }}}
and
{{{ s + 1 = 4 }}}
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The speed of the slower boy is 3 mi/hr
The speed of the faster boy is 4 mi/hr
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check:
Equation for slower boy:
{{{ d[1] = 3*1 }}}
{{{ d[1] = 3 }}}
and
{{{ d[2] = 4*1 }}}
{{{ d[2] = 4 }}}
and
{{{ d[1] + d[2] = 3 + 4 }}}
{{{ d[1] + d[2] = 7 }}} mi