Fixing Android Studio radio button bug - android-studio

Question

I have 4 radio buttons in my app, which when when clicked excecutes the onClick method tipamount1:
rad1.setChecked(false);
rad2.setChecked(false);
rad3.setChecked(false);
rad4.setChecked(false);
Snackbar snackbar = Snackbar
.make(screen, "please enter a valid bill amount", Snackbar.LENGTH_LONG);
snackbar.show();
}
String valueStr = totalinput.getText().toString();
Double value = Double.parseDouble(valueStr);
tipamount = 0.12*value;
totalwithtip = tipamount+value;
double roundOff = Math.round(tipamount * 100.0) / 100.0;
double roundOff2 = Math.round(totalwithtip * 100.0) / 100.0;
tipamounttext.setText(String.format("%d",roundOff));
totalwithtiptext.setText(String.format("%",roundOff2));
rad2.setEnabled(false);
rad3.setEnabled(false);
rad4.setEnabled(false);
}
When I run the app and click on the first radiobutton, below is the error I am getting:
Process: com.example.tipsplit, PID: 1967
java.lang.IllegalStateException: Could not execute method for android:onClick
at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:414)
at android.view.View.performClick(View.java:7448)
at android.widget.CompoundButton.performClick(CompoundButton.java:144)
at android.view.View.performClickInternal(View.java:7425)
at android.view.View.access$3600(View.java:810)
at android.view.View$PerformClick.run(View.java:28305)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:223)
at android.app.ActivityThread.main(ActivityThread.java:7656)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:409)
at android.view.View.performClick(View.java:7448) 
at android.widget.CompoundButton.performClick(CompoundButton.java:144) 
at android.view.View.performClickInternal(View.java:7425) 
at android.view.View.access$3600(View.java:810) 
at android.view.View$PerformClick.run(View.java:28305) 
at android.os.Handler.handleCallback(Handler.java:938) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:223) 
at android.app.ActivityThread.main(ActivityThread.java:7656) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947) 
Caused by: java.util.IllegalFormatConversionException: d != java.lang.Double
at java.util.Formatter$FormatSpecifier.failConversion(Formatter.java:4403)
at java.util.Formatter$FormatSpecifier.printInteger(Formatter.java:2885)
at java.util.Formatter$FormatSpecifier.print(Formatter.java:2839)
at java.util.Formatter.format(Formatter.java:2524)
at java.util.Formatter.format(Formatter.java:2459)
at java.lang.String.format(String.java:2870)
at com.example.tipsplit.MainActivity.tipamount1(MainActivity.java:69)
at java.lang.reflect.Method.invoke(Native Method) 
at androidx.appcompat.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:409) 
at android.view.View.performClick(View.java:7448) 
at android.widget.CompoundButton.performClick(CompoundButton.java:144) 
at android.view.View.performClickInternal(View.java:7425) 
at android.view.View.access$3600(View.java:810) 
at android.view.View$PerformClick.run(View.java:28305) 
at android.os.Handler.handleCallback(Handler.java:938) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:223) 
at android.app.ActivityThread.main(ActivityThread.java:7656) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:947) 
After looking at the line at com.example.tipsplit.MainActivity.tipamount1(MainActivity.java:69) at java.lang.reflect.Method.invoke(Native Method) , I found that it is the line tipamounttext.setText(String.format("%d",roundOff)); that is causing this error. However I do not know why tipamounttext is responsible since I have it defined in my onCreate as shown below:
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
totalinput = findViewById(R.id.totalamountinput);
tipamounttext = findViewById(R.id.tipamountresult);
totalwithtiptext = findViewById(R.id.totalwithtipresult);
rad1 = findViewById(R.id.twelvepercent);
rad2 = findViewById(R.id.fifteenpercent);
rad3 = findViewById(R.id.eighteenpercent);
rad4 = findViewById(R.id.twentypercent);
screen = findViewById(R.id.totalbillinput);
}