float x = 7001.1;
float DIV = 0.00;
float RPM = 0;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);

}

void loop(){

  DIV = (x / 7);
  RPM = DIV * 60;

Serial.print(x);
Serial.print(" / 7 = ");
Serial.println(DIV);

Serial.print("RPM = ");
Serial.print(DIV);
Serial.print(" * 60 = ");
Serial.println(RPM, 0);

delay(600000);
}