Posted by **Jane** on Wednesday, February 3, 2010 at 1:57pm.

Andrew arranged the number 1, 2, 3, ...11, 12 into six pairs so that the sum ofany two numbers in a pair is prime and no two of these primes are equal. find the primes and the pairs

- Maths -
**drwls**, Wednesday, February 3, 2010 at 2:53pm
I had to solve this by "trial and error" and finally came up with this. There many be other solutions.

1 + 4 = 5

2 + 5 = 7

3 + 8 = 11

6 + 7 = 13

9 + 10 = 19

11 + 12 = 23

Other prime-number-sum combinations possible would have been 3 and 17, but by forming them I had to use numbers twice or get duplicate sums.

- Maths -
**Rosie**, Monday, August 1, 2016 at 12:36am
(5,8);(3,2);(1,6);(9,10);(4,7);(11,12).

5+8=13

3+2=5

1+6=7

9+10=19

4+7=11

11+12=23

Hope that helps!!!!! :)

## Answer This Question

## Related Questions

- math - The Twin Prime Conjecture, which has not been proven, argues that there ...
- math - every number greater than 2 can be written as the sum of two prime ...
- MATHS - The+sum+of+two+numbers+is+30+six+less+than+twice+the+smaller+number+is+...
- math - Can someone help me with prime and composite numbers? Prime numbers are ...
- math - Two consecutive odd primes, such as 11 and 13, are called a pair of "twin...
- algebra - A pair of emirps consists of two prime numbers such that reversing ...
- MATH! - The sum of two prime numbers is the prime number 89,563. Find the ...
- Number Sentence - In a 4-digit number, the two greatest place-value digits are 2...
- high school (math) - Match the mathematical expression with its translation. 1. ...
- making dot arrays - what are the numbers calleed that we cant use in 2 - row ...

More Related Questions