2/3 is simplest form. You cannot divide any more to find the simplified form.
Answer:

Step-by-step explanation:
first you subtract 7 from 7 and 12

then you get 
(btw the variable always goes first with these problems)
so the final answer would be 
Answer: 9.725 ≤ x ≤ 9.734
Step-by-step explanation:
We know that 9.73 is rounded, then we need to look at the next digit after the last one of 9.73, this would be the third digit after the decimal point.
We know that if this digit is smaller than 5, then we round down.
Then the largest number that can be rounded down to 9.73 is:
9.734
Now we want to find the smallest number that can be rounded up to 9.73
We know that if the next digit is 5 or bigger, then we round up.
Then the number 9.725 is rounded up to 9.73
And this is the smallest number that can be rounded up to 9.73
Then the error interval is:
9.725 ≤ x ≤ 9.734
The greatest number is 28 people
Answer:
Maggie has seen at least 1620 birds.
Step-by-step explanation:
Ok since Maggie sees 36 birds each trip that means she sees 108 birds every year since she takes 3 trips each year. 36×3=108
If she has been doing this for 15 years she has seen at least 1620 birds because 108×15=1620