SOLUTION: How can i get the numbers 20,17,39,and 13 by using 5,2,8,and 4 only once.I can only add,subtract,and multiply once.

Question 380926: How can i get the numbers 20,17,39,and 13 by using 5,2,8,and 4 only once.I can only add,subtract,and multiply once.
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Generating 20:

(5+2)*4-8 = 7*4-8 = 28-8 = 20

or

(5-2)*4+8 = 3*4+8 = 12+8 = 20

or

(8-5+2)*4 = 5*4 = 20

Generating 17:
5+2*8-4 = 5+16-4 = 21-4 = 17

Generating 39:
It is NOT possible to generate 39 using the given numbers and rules above. I've tried all possible combinations and cannot get 39 (you could get 39 if you allowed two + symbols since 8*4+5+2 = 39)

Generating 13
(8-4)*2+5 = 4*2+5 = 8+5 = 13

RELATED QUESTIONS
How do I get the answer 1797 using numbers 86254 only once each? You can subtract, add,... (answered by greenestamps)

I can use the numbers 0, 1, 2, and 6. I have to use each number and can only use each... (answered by Alan3354,fractalier)

I can use the numbers 0, 1, 2, and 6. I have to use each number and can only use each... (answered by fractalier,MathTherapy)

I have the numbers 8,8,4,9. I have to get the sum 24 by using the numbers only once. I... (answered by solver91311)

I can use the numbers 0, 1, 2, and 6. I have to use each number and can only use each... (answered by Alan3354,MathTherapy)

list three digit numbers that can be written using each of the digits 2,5,and 8 once and... (answered by stanbon)

create the number 24 using the numbers 1, 3, 4, and 6. You can add, subtract, multiply... (answered by sdmmadam@yahoo.com)

How many 3-digit numbers greater than 400 can you make using the numbers 2, 1, 4 and 3... (answered by Fombitz)

The question is: How many EVEN, 4 digit numbers can you create using 1, 2,3, and 5 only... (answered by edjones)