document.write( "Question 884857: a train travel 68 km/h at an average speed of 51 km/h.It than travel another 20 km at an average speed of 40 km/h before reaching its destination. Calculate the average speed for the whole journey. \n" ); document.write( "
Algebra.Com's Answer #534714 by JulietG(1812)\"\" \"About 
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At 51kmh, the train would need to travel 1\"1%2F3\"hours to cover 68km. [68-51= 17. 17 is \"1%2F3\"of 51.]
\n" ); document.write( "At 40kmh, the train would need to travel \"1%2F2\"hour to cover 20km [20/40]
\n" ); document.write( "Total travel time is 1\"5%2F6\"hours (or 1 hour 50 minutes).
\n" ); document.write( "In that time, total distance is 88km
\n" ); document.write( "88km / 1.8333 (converted the fraction to decimal for ease of use) = 48kmh average speed.
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