mathsteps: figure out what to do about errors from rounding midway through

Blocked on a new parse tree that Kevin is working on. When we have the new tree, we’ll be able to add clearer information about approximate values and won’t have to round!

---

so it’s good pedagogically to round partway through, but then we can get the wrong answer in the end!

e.g. this gives us 6.399 when it should actually be 6.4 😦

x - 3.4 = ( x - 2.5)/( 1.3)

steps (approximately, to give an idea of why this happens):

• x - 3.4 = x/1.3 - 2.5/1.3
• x - 3.4 = x/1.3 - 1.9231 (maybe we wouldn’t divide here, but how would we make that call easily?)
• …
• (1 - 1/1.3) x = 3.4 - 1.9231
• …
• 0.2308x = 1.4769
• …
• x = 6.399

I’m not really sure what the best pedagogical solution is! having really long numbers in the middle wouldn’t really be great. What would we want to show the user?