DD9 says she hates math and can't do it, etc. etc. etc but then spends time figuring out how many minutes are in a year and how many minutes a trip will take if we have 150 miles to go and are traveling at 75 mph!
She too got stuck on the show your work stuff when it was simple arithematic, and even now is more accurate in her head than on paper. I wish I could figure out a way to increase her confidence in math and then I think her ability to write down her reasoning would increase because she doesn't like to get things wrong, so she doesn't want to show her work.