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One car travels 270 miles in the same amount of time it takes a second car traveling 6 miles per hour slower than the first to go 234 miles. What are the speeds of the cars?

2 Answers
Feb 9, 2018

Answer:

Car one speed is x, and car 2 speed is x-6
Both cars travel same amount of time. d= v x t so t= d/v
set the two times equal and solve for x

Explanation:

#270/x = 234/(x-6)#

#270(x-6) = 234x#

#270x-1620 = 234x#

#36x-1620= 0#

#36 x = 1620#

#x= 45mph#

Feb 9, 2018

Answer:

#45" mph and "39" mph"#

Explanation:

#"using the formula"#

#• " average speed (S)"="distance (D)"/"time (T)"#

#T" is a constant quantity here"#

#color(blue)"car 1"#

#S=270/TrArrST=270to(1)#

#color(blue)"car 2"#

#S-6=234/TrArrST-6T=234to(2)#

#"subtract "(2)-(1)#

#rArr6T=270-234=36#

#rArrT=36/6=6" hours"#

#rArrcolor(blue)"car 1"toS=270/6=45" mph"#

#rArrcolor(blue)"car 2 "toS=234/6=39" mph"#