20% of 30 is 6. 30-6 is 24. He now works for 24 hours! Please mark brainliest!!!
The answer is a! i hope this helps you!
Number of ways to select 3 books from 13 books for adoption is 286 .
<u>Step-by-step explanation:</u>
A Permutation is an ordered Combination. When the order does matter it is a Permutation. There are basically two types of permutation:
- Repetition is Allowed: such as the lock above. It could be "333".
- No Repetition: for example the first three people in a running race. You can't be first and second.
Formula is given by:
, where n is the number of things to choose from, and we choose r of them, no repetitions, order matters. Here , n=13 , r=3.
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∴ Number of ways to select 3 books from 13 books for adoption is 286 .
D: We solve this in exactly the same way in which we solved the previous area problem. Side length is s, area is s^2. Here, side length is 5 in; area is 25 in^2.
the problem does say, however, not to include units in your answer. Thus, just write "25."
I think it is the first one: Different bar widths.