SOLUTION: Find the range of values of x .A cyclist travels xkm in 4 hrs ,then ( x 60 )km in 7 hrs. Its average speed does not exceed 150km/h

Algebra ->  Inequalities -> SOLUTION: Find the range of values of x .A cyclist travels xkm in 4 hrs ,then ( x 60 )km in 7 hrs. Its average speed does not exceed 150km/h       Log On


   

Question 962283: Find the range of values of x .A cyclist travels xkm in 4 hrs ,then ( x 60 )km in 7 hrs. Its average speed does not exceed 150km/h
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

the range of values of x .
A cyclist travels xkm in 4h ,=>%28x%2F4%29%28km%2Fh%29
then +60xkm+(I guess you have that) in 7h=>%2860x%2F7%29%28km%2Fh%29
Its average speed does not exceed 150%28km%2Fh+%29
%28x%2F4%29%28km%2Fh%29%2B%2860x%2F7%29%28km%2Fh%29%3C=150%28km%2Fh+%29
%287x%2F28%29%28km%2Fh%29%2B%28240x%2F28%29%28km%2Fh%29%3C=150%28km%2Fh+%29
%28%287x%2B240x%29%2F28%29%28km%2Fh%29%3C=150%28km%2Fh+%29
247x%3C=28%2A150
x%3C=4200%2F247
x%3C=17.00404858299595
the range of values of x will be numbers less and equal than 17.00404858299595, which are 17.00404858299595,17,16,15,......

check:
%2817%2F4%29%28km%2Fh%29%2B%28%2860%2A17%29%2F7%29%28km%2Fh%29%3C=150%28km%2Fh+%29

%284.251012145748988%2B145.748987854251%29%28km%2Fh%29%3C=150%28km%2Fh+%29
150%28km%2Fh%29%3C=150%28km%2Fh+%29
or, to make it easier, round it to
x%3C=17
the range of values of x will be numbers less and equal than 17, which are 17,16,15,......
check:
%2817%2F4%29%28km%2Fh%29%2B%28%2860%2A17%29%2F7%29%28km%2Fh%29%3C=150%28km%2Fh+%29
%2817%2F4%29%28km%2Fh%29%2B%281020%2F7%29%28km%2Fh%29%3C=150%28km%2Fh+%29
4.25%28km%2Fh%29%2B145.714%28km%2Fh%29%3C=150%28km%2Fh+%29
149.964%28km%2Fh%29%3C=150%28km%2Fh+%29