Each with each

Five pupils from 3A class played table tennis. How many matches did they play with each other?

Result

n =  10

Solution:

z=5 n=z⋅ (z−1)2=5⋅ (5−1)2=10z = 5 \ \\ n = \dfrac{ z \cdot \ (z-1) }{ 2 } = \dfrac{ 5 \cdot \ (5-1) }{ 2 } = 10

Try another example


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!





Leave us a comment of this math problem and its solution (i.e. if it is still somewhat unclear...):

Showing 0 comments:
1st comment
Be the first to comment!
avatar




Tips to related online calculators
Would you like to compute count of combinations?

Following knowledge from mathematics are needed to solve this word math problem:

Next similar math problems:

  1. Cages
    guineapig Honza had three cages (black, silver, gold) and three animals (guinea pig, rat and puppy). There was one animal in each cage. The golden cage stood to the left of the black cage. The silver cage stood on the right of the guinea pig cage. The rat was in the
  2. Italian writer
    books_11 There were 17 children in the barracks with an Italian writer. 6 children ordered a book in an Italian original and 12 children in the translation. How many children ordered a book in both languages if the three children did not order it?
  3. Write decimals
    numbers_34 Write in the decimal system the short and advanced form of these numbers: a) four thousand seventy-nine b) five hundred and one thousand six hundred and ten c) nine million twenty-six
  4. Digits
    pin_keyboard How many odd four-digit numbers can we create from digits: 0, 3,5,6,7?
  5. No. 215
    215_num From the number 215 we can create a four-digit number that among its numbers manually type any other digit. Thus, we created two four-digit numbers whose difference is 120. What two four-digit numbers that might be?
  6. Football team
    trenyrky Football team has in store black, purple and orange shirts, blue and white shorts and striped and gray socks. How many different outfits players may start?
  7. Unknown number 16
    numbers_35 My number's tens is three times more then ones My number's ones is twice the number of thousands and my number's hundreds is half the number of of tens. I have two ones. which number am I?
  8. Gloves
    rukavice_1 Petra has ten pairs of gloves in the closet. Six pairs are blue, 4 pairs are yellow. How many pieces of gloves need to be pulled out at least when she pull them out in the dark and want to have one complete one color pair?
  9. Addition of Roman numbers
    roman Added together and write as decimal number: LXVII + MLXIV
  10. Roman numerals
    roman_1 Write numbers written in Roman numerals as decimal.
  11. Sum of the digits
    numbers2 How many are two-digit natural numbers that have the sum of the digits 9?
  12. Subtraction
    plusminus_1 Test what do you know about the subtraction of two numbers: a) make a difference if the minuend 4,307,288 and subtrahend is 472008 b) minuend is 4000 more than subtrahend. What's the difference? c) the difference is 38900 less than the minuend. What is th
  13. Division
    numbers_36 Which number in division 16 give 12 and the rest 3?
  14. Seven times
    numberline_12 Which number seven times is just as higher as 27, how much is smaller than 29?
  15. Hockey
    hokej Hockey match ended 8:2. How many different matches could be?
  16. Mystery number
    numbers2_38 A mystery number is between 800 and 920. No digits are the same. The difference of the number is 5. What is the mystery number?
  17. Popsicles
    nanuky Francis went to buy ice lollies. If he buy 8 popsicles he missed 4 USD. When he buy 7 popsicles, got back 1 USD. How many USD was a popsicle?