I Calculate A 100% Chance Of Failure

(I work as an accountant and have a very… interesting coworker. I take her calculator and try to make my coworker count in her head.)

Me: “What’s 50% of 18?”

Coworker: “I can’t count without my calculator!”

Me: “Just try, what’s 50% of 18?”

Coworker: “6?”

Me: “What’s 6 plus 6?”

Coworker: “12.”

Me: “So what’s 50% of 18?”

Coworker: “8.”

Me: “And what’s 8 plus 8?”

Coworker: “I can’t do it without my calculator!”

Me: “I won’t give it back to you unless you tell me.”

Coworker: “16.”

Me: “So what’s 50% of 18?”

Coworker: “9.”

Me: “Okay, and what’s 18 plus 9?”

Coworker: “I. Can’t. Count. Without. My. CALCULATOR!”