What is the sum of X+XX+XXX+XXXX?

Read also:

• What's the biggest myth about illegal immigrants?
• Scientists Uncover Hundreds New Giant Viruses That May Be Quietly Threatening Ocean Life - Indian Defence Review
• Evan Engram embraces the “Joker” role in the Broncos’ offense - NBC Sports
• ‘Godfather’ of AI Yoshua Bengio says latest models lie to users - Financial Times
• Video: Do You Even Need A Pro Controller For The Switch 2? - Nintendo Life
• Steam gamers given 24 hours to grab hit game completely free - GAMINGbible
• Taylor Swift Owns Two Versions of Four Albums. Now What? - Billboard
• The No. 1 Supplement Causing Dangerous Liver Damage, Doctors Warn - bestlifeonline.com
• The Cause of Alzheimer's Might Be Coming From Within Your Mouth - ScienceAlert
• Senate to Review Trump ‘Revenge’ Tax Worrying Wall Street - Bloomberg