Percent error is calculated using
((Actual - predicted) / actual) * 100
In this case, the actual value of the number of pages he read is 20. The expected value was 23. So simply plug in:
((20 - 23) / 20) * 100 = -15%
Please don’t forget to like and mark brainliest
Step-by-step explanation:
To multiply the fractions, like

Multiply the top,
then multiply the bottom.

Try to use a calculator if you aren't arithmetic heavy, but I suggest you to try to remember them because they are going to be helpful for courses like Algebra, Calculus, Statistics, etc.
To divide fractions, like

You take the top number,

Then you flip the bottom number,

Then multiply the two

And that is your answer. Comment if you need more clarification
Answer:
9 and a half inches
Step-by-step explanation:
Just count via the ruler!
It is A
Hope this helps :3