"If x is the decimal 8.1d5, with d as an unknown digit, and x rounded to the nearest tenth is equal to 8.1, which digits could not be the value of d?"
Official answers include 5, 6, 7, 8, 9.
But shouldn't also 4 be included?
8.145 -> 8.15 -> 8.2
The thousandths digit (5) actually rounds up the hundredths digit so only 1, 2, 3 would actually produce a 8.1.