How many 2

How many three lettered words can be formed from letters A B C D E G H if repeats are:
a) not allowed
b) allowed

Correct result:

n1 =  210
n2 =  343

Solution:

$n_{1}=7 \cdot \ 6 \cdot \ 5=210$
$n_{2}=7 \cdot \ 7 \cdot \ 7=343$

Our examples were largely sent or created by pupils and students themselves. Therefore, we would be pleased if you could send us any errors you found, spelling mistakes, or rephasing the example. Thank you!

Please write to us with your comment on the math problem or ask something. Thank you for helping each other - students, teachers, parents, and problem authors.

Tips to related online calculators

Next similar math problems:

• Three workplaces
How many ways can we divide nine workers into three workplaces if they need four workers in the first workplace, 3 in the second workplace and 2 in the third?
• A student
A student is to answer 8 out of 10 questions on the exam. a) find the number n of ways the student can choose 8 out of 10 questions b) find n if the student must answer the first three questions c) How many if he must answer at least 4 of the first 5 ques
• Word MATEMATIKA
How many words can be created from the word MATEMATIKA by changing the order of the letters, regardless of whether or not the words are meaningful?
• Permutations without repetition
From how many elements we can create 720 permutations without repetition?
• Peak
Uphill leads 2 paths and 1 lift. a) How many options back and forth are there? b) How many options to get there and back by not same path are there? c) How many options back and forth are there that we go at least once a lift?
• Cards
How many ways can give away 32 playing cards to 7 player?
On the menu are 12 kinds of meal. How many ways can we choose four different meals into the daily menu?
• PIN - codes
How many five-digit PIN - code can we create using the even numbers?
• Division
Division has 18 members: 10 girls and 6 boys, 2 leaders. How many different patrols can be created, if one patrol is 2 boys, 3 girls and 1 leader?
• 7 heroes
9 heroes galloping on 9 horses behind. How many ways can sort them behind?
• Football league
In the 5th football league is 10 teams. How many ways can be filled first, second and third place?
• Neighborhood
I have 7 cups: 1 2 3 4 5 6 7. How many opportunities of standings cups are there if 1 and 2 are always neighborhood?
• Balls
From the urn in which are 7 white balls and 17 red, gradually drag 3-times without replacement. What is the probability that pulls balls are in order: red red red?
• Hearts
5 cards are chosen from a standard deck of 52 playing cards (13 hearts) with replacement. What is the probability of choosing 5 hearts in a row?
• Tokens
In the non-transparent bags are red, white, yellow, blue tokens. We 3times pull one tokens and again returned it, write down all possibilities.
• Virus
We have a virus that lives one hour. Every half hour produce two child viruses. What will be the living population of the virus after 3.5 hours?
• School trip
The class has 19 students. What different ways students can be accommodated in the hostel, where available 3× 2-bed, 3× 3-bed and 1× 4-bed rooms. (Each room has its unique number)