Examples --
float freq;
float ftime;
void setup() {
Serial.begin(19200);
freq = 1000.00000;
ftime = 1.0 / freq;
Serial.println(ftime, 6);
freq = 250000;
ftime = 1.0/ freq;
Serial.println(ftime, 6);
freq = 1000000;
ftime = 1.0/ freq;
Serial.println(ftime, 6);
}