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 .
Ok so
ratio
35/200=x/3000
7/40=x/3000
multiply both sides by 12000
2100=4x
divide both sides by 4
525=x
aprox 525 people
Answer:
x= - square root 141 or x= square root 141
Answer:
tăng lên 5.000 nghìn đồng
Step-by-step explanation:
mỗi chuyến bay có 0.5% hành khách mất hành lí
mỗi người đòi bồi thường 1.000.000 đồng
do đó vẽ mỗi người tăng lên :0.5%×1.000.000=5.000