# Maths Puzzle - Logic

Somebody asked me this puzzle, but they don't have answer to it.

1+2+3+4 = 61

2+3+4+5 = 52

3+4+5+6 = 51

4+5+6+7 = 50

7+8+9+10 = ?

I want to know whether my reasoning and solution is correct or not

• We need to find out what 34 is equal to

• The logic is 4th equation - 2nd equation , then add the result to 2nd equation

• Now, we know what 22 equals to
• Now add, the 4th equation , we know what 44 equals to
• Now, subtract with first equation, and you get what 34 equals to
• Which is 39
• $34{}{}{}{}{}$ PS: the others are wrong. Jan 17, 2016 at 5:51
• I reposted this at puzzling.se here puzzling.stackexchange.com/questions/25449/… Jan 17, 2016 at 5:57
• ????? 4th eq - 2nd = 2 + 2 + 2 +2 = -2. then add to 2nd => 4+5+6+7 = 52. "now we know what 22 equals to-" ??? "now add the 4th equation" => 8 + 10 + 12 + 14 = 104. Now subtract with the first equation => 7 + 8 + 9 + 10 = 33. ... I don't understand your explanation. Jan 17, 2016 at 5:59
• Huh? "We need to find out what 34 is equal to" Why? where did 34 come from? "4th eq - 2 eq and ad to the 2nd eq" Um, that just give you the 4th equation all over again. (x - y) + y = x ??? Now we know what 22 is equal to? Huh? Where did you get the number 22 from? Where are you getting these numbers? I have the slightest idea what you are doing. What is the question??? How is 39 an answer? What are you doing? Jan 17, 2016 at 6:33
• Um.. so you are assuming that 1+2+3+4 = 10 => 61;2+3+4+5 =14=> 52; 18 => 51; and 22 => 50; 34=>x? So you figure \$34 = 2*22 - 10 => 2*50 - 61 = 39? Okay, but why not 34 = 3*10 + 14 => 183 + 52 = 235? That answer is just as logical and consistent. Jan 17, 2016 at 6:55