Since forever, basically.
I can do simple addition, single digit subtraction, multiplication of 9s up to 10 (because of the sequencing of the numbers) and fractions/decimals in the 25 and 4 range (like 4 quarters to a dollar, 25 cents, etc). But it takes me a while, people usually get impatient and just give me the answer.
That's it though. Anything else, multiplication, division, alegbra.. everything else is either "Calculator Required" or "I Have No Way To Understand What This Is". I likely have dyscalculia. I have all the symptoms/signs. As a child my parents spent hundreds and hundreds of dollars on all kinds of programs, sent me to special classes, special teachers. Bupkis. They wasted their money every time, nothing ever worked.
OH. And I can't remember number sequences of any kind unless they have a specific rhythm. Even simple phone numbers like 247 2447 trip me up. I had to write that extra slow and say it several times in my head. I have a light stutter, and I literally stutter in my HEAD as well as out loud when I say numbers that repeat like that, because I'm never sure if I got the sequence correct. Hell, I even turn double digit numbers backwards a lot. Like I'll hear "87" and it'll become "78".
Thank god my Husband's cell number is a really good rhythmic sequence, it's easy to remember.
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"So much of what she'd thought was truth before was merely tricks. No more than clever ways of speaking to the world. They were a bargaining. A plea. A call. A cry."
I am a Bookwyrm.