Pavan Putra Boy Pavan Putra Boy - 6 months ago 48
Java Question

Maths query in java

I am not very good in maths . So please don't mind my mistakes !
This is the question :

Speedy kings are a racing group. Their leader John owns a Suzuki
Hayabusa which has a maximum speed of 300 kmph. The leader of the
rival group, Ranson owns a Ducati whose maximum speed is 280 kmph.
John makes n rounds of 10km track. How much time(in minutes) will
Ranson take to complete the same distance covered by John. Take the
value of n as input from the user. Sample Input: 4 Sample Output: 8

Now this is my solution :

class speedyKings{
public static void main(String args[]){
Scanner in=new Scanner(;
int ducs=280;
int hays=300;
int total_dist=10000;
int n=in.nextInt();
double time=((10000*n)/280);

But it is not giving the right output can anybody help ?


Your best bet is to take small steps to get to the right value. You can use appropriately named variables to remember what you're looking at and working with:

Scanner in = new Scanner(;
int laps = in.nextInt();
double speedInKph = 280; // km/h
double lapLength = 10000; // meter
double speedInMpS = speedInKph * 1000 / 3600; // m/s
double secondsPerLap = lapLength / speedInMpS; // m / (m/s) = s
double minutesPerLap = secondsPerLap / 60;
double minutes = minutesPerLap * laps;

System.out.println("Minutes: " + minutes);