Sierra rode 15 mi in 1.5 hr. Joe rode 38 mi in 3.5 h. Justice rode 22 mi in 2.25 hr. Who had the fastest average speed?

1 Answer
Sep 12, 2017

#"Joe"#

Explanation:

#"calculate the average speed of each cyclist using"#

#color(red)(bar(ul(|color(white)(2/2)color(black)("average speed "=("distance")/("time"))color(white)(2/2)|)))#

#• " Sierra"#

#"average speed "=(15" mi")/(1.5" hr")=10"mph"#

#• " Joe "#

#"average speed "=(38" mi")/(3.5" hr")#

#color(white)("average speed")=38/(7/2)=38/1xx2/7=76/7=10 6/7" mph"#

#• " Justice"#

#"average speed "=(22" mi")/(2.25" hr")=22/(9/4)#

#color(white)(xxxxxxxxx)=22/1xx4/9=88/9=9 6/7" mph"#

#"Joe had the fastest average speed"#