Question 1162960
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The other tutor demonstrates one good algebraic method for solving the problem: setting the two time (=distance/rate) expressions equal to each other and solving the equation.<br>
{{{260/(r+3) = 200/(r-3)}}}<br>
If you are good with mental arithmetic, the problem can be solved without algebra by setting up the problem differently.<br>
Since the times are the same, the ratio of distances is equal to the ratio of the speeds:<br>
{{{260/200 = (r+3)/(r-3)}}}<br>
The difference between numerator and denominator on the right is 6 -- so write the fraction on the left as an equivalent fraction in which the difference between numerator and denominator is also 6:<br>
{{{26/20 = (r+3)/(r-3)}}}<br>
r+3 = 26 and r-3 = 20...<br>
ANSWER: r = 23<br>