Answer:
9.23712
Explanation:
First it asks you to round to the nearest thousandth of 8.23678. So, with decimals it is tenths, hundreths, then thousandths. So the 3rd decimal place. You then will compare look at the 4th decimal place, 7, and compare it to 5. Since 7 is greater than 5, the 3rd decimal space goes up, being 8.237. Now you add the 1.00012 to get 9.23712.