Can't convert it from Fahrenheit to Celcius in Android emulator

Here's my code: It only works when i convert it from Fahrenheit to Celcius but it doesn't work when i convert it from Celcius into Fahrenheit. I've tried for so many times but it still doesn't work for me.

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.converter_second);

    rb_celcius = (RadioButton) findViewById(R.id.radioButton_celcius);
    rb_fahrenheit = (RadioButton) findViewById(R.id.radioButton2_fahrenheit);
    btn_convert = (Button) findViewById(R.id.button3_convert);
    btn_clear = (Button) findViewById(R.id.button5_clear);
    edTxt_amount = (EditText) findViewById(R.id.editText_amount);
    txtVw_answer = (TextView) findViewById(R.id.textView7_answer);

    btn_convert.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            double dblFahrenheit = 0;
            double dblCelcius = (5.0 / 9) * (dblFahrenheit - 32);
            double dblConvertedTemp = 0;
            double dblFahConversion;
            if (v == btn_convert) {
                if (rb_celcius.isChecked()) {
                    String strFah = edTxt_amount.getText().toString();
                    if (!strFah.isEmpty()) {
                        {
                            dblFahrenheit = Double.parseDouble(strFah);
                        }
                        if (dblFahrenheit <= 212) {
                            dblConvertedTemp = (5.0 / 9.0) * (dblFahrenheit - 32);
                            txtVw_answer.setText("The answer is " + dblConvertedTemp);

                        } if (rb_fahrenheit.isChecked()) {
                            String strCel = edTxt_amount.getText().toString();
                            if (!strCel.isEmpty()) {
                                {
                                    dblCelcius = Double.parseDouble(strCel);
                                }
                                if (dblCelcius <= 100) {
                                    dblFahConversion = dblCelcius * (9.0 / 5.0) + 32;
                                    txtVw_answer.setText("The answer is" + dblFahConversion);
                                }
                            }
                            else if (v == btn_clear){
                                rg_group.clearCheck();
                                txtVw_answer.setText("");
                        }

                    }
                }
            }
        }

        }
    });
}

}