Question 1101363
d, the total length of the journey


{{{(3/8)d+(1/8)d+45=d}}}

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{{{(1/2)d+45=d}}}

{{{d+90=2d}}}

{{{highlight(d=90)}}}


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check:
{{{90*3/8+90/8+45=90}}}
{{{(1/2)*90+45=90}}}
{{{45+45=90}}}
checks right