Number of Possible Sums with 1-15 Cards

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In summary, the conversation discusses the number of distinct sums that can be made using a set of cards with numbers 10, 100, and 500. The original answer given is 143, but the speaker argues that their logic leads to only 141 distinct sums. They ask for clarification on which 2 distinct sums were omitted and if the answer of 143 is incorrect. They also mention a formula that could potentially be used to find the number of distinct sums.
  • #1
WMDhamnekar
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There are 8 cards with number 10 on them, 5 cards with number 100 on them and 2 cards with number 500 on them. How many distinct sums are possible using from 1 to all of the 15 cards?Answer given is 143. But my logic is for any sum, at least 2 numbers are needed. So, there are $\binom{15} {2} + \binom{15}{3}+...\binom{15}{15} $ distinct sums. So, I think answer 143 is wrong.
What is your opinion?
 
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  • #2
[tex]\begin{pmatrix}15 \\ 2 \end{pmatrix}[/tex] is the number of sums of two of the numbers, [tex]\begin{pmatrix}15 \\ 3 \end{pmatrix}[/tex] is the number of sums of three of the numbers, etc. But they won't be distinct sums.
 
  • #3
Dhamnekar Winod said:
There are 8 cards with number 10 on them, 5 cards with number 100 on them and 2 cards with number 500 on them. How many distinct sums are possible using from 1 to all of the 15 cards?Answer given is 143. But my logic is for any sum, at least 2 numbers are needed. So, there are $\binom{15} {2} + \binom{15}{3}+...\binom{15}{15} $ distinct sums. So, I think answer 143 is wrong.
What is your opinion?

The directions clearly state from 1 to 15, so their solution is based on that premise.
 
  • #4
CountryBoy said:
[tex]\begin{pmatrix}15 \\ 2 \end{pmatrix}[/tex] is the number of sums of two of the numbers, [tex]\begin{pmatrix}15 \\ 3 \end{pmatrix}[/tex] is the number of sums of three of the numbers, etc. But they won't be distinct sums.

Hello,

I have computed 141 distinct sums. But the answer is 143. Which 2 distinct sums i omitted, would you tell me? Is the answer 143 wrong? All the 141 distinct sums are

20,30,40,50,60,70,80,110,120,130,140,150,160,170,180,200,210,220,230,240,250,260,270,280,300,310,320,330,340,350,360,370,380,400,410,420,430,440,450,460,470,480,500,510,520,530,540,550,560,570,580,600,610,620,630,640,650,660,670,680,700,710,720,730,740,750,760,770,780,800,810,820,830,840,850,860,870,880,900,910,920,930,940,950,960,970,980,1000,1010,1020,1030,1040,1050,1060,1070,1080,1100,1110,1120,1130,1140,1150,1160,1170,1180,1200,1210,1220,1230,1240,1250,1260,1270,1280,1300,1310,1320,1330,1340,1350,1360,1370,1380,1400,1410,1420,1430,1440,1450,1460,1470,1480,1500,1510,1520,1530,1540,1550,1560,1570,1580.

I know one formula $\binom{r+n-1}{r-n+1}$ which computes distinct sums, where n=cells and r= balls. How to use that here? Or is there any other formula?
 
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FAQ: Number of Possible Sums with 1-15 Cards

What is the maximum possible sum with 15 cards?

The maximum possible sum with 15 cards is 120, which is achieved by adding all the numbers from 1 to 15.

How many different combinations of cards can result in a sum of 50?

There are 9 different combinations of cards that can result in a sum of 50. These are: 5+6+7+8+9+10+11, 6+7+8+9+10+11, 7+8+9+10+11, 8+9+10+11, 9+10+11, 10+11, 11, 5+6+7+8+9+10+11+12, and 6+7+8+9+10+11+12.

Is there a pattern to the number of possible sums with 1-15 cards?

Yes, there is a pattern to the number of possible sums with 1-15 cards. The number of possible sums increases by 1 with each additional card, starting with 1 possible sum with 1 card and ending with 15 possible sums with 15 cards.

How many possible sums are there with 1-15 cards?

There are a total of 120 possible sums with 1-15 cards. This can be calculated by using the formula n(n+1)/2, where n is the number of cards (in this case, n=15).

Can the same sum be achieved with different combinations of cards?

Yes, the same sum can be achieved with different combinations of cards. For example, a sum of 10 can be achieved with the combination of 1+9, 2+8, 3+7, 4+6, and 5+5. This is known as a "combinatorial explosion" and is a common occurrence in mathematics.

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