Respuesta :
They also add the previous sum....1+4=5 and 5+5+2 is 12....12+6+3 is 21 and so on (:
Answer:
The puzzle is first add the current two numbers and then add their sum to result obtained in previous step.
Step-by-step explanation:
1 + 4 = 5
2 + 5 = 12
12 is obtained by adding 2 + 5 = 7 and adding the result obtained in previous result which is 5 to 7
⇒ 7 + 5 = 12
Now, 3 + 6 = 21
21 is obtained by first adding 3 + 6 = 9 and the previous result obtained is 12
So adding 12 to 9 ⇒ 12 + 9 = 21
Hence, The puzzle is first add the current two numbers and then add their sum to result obtained in previous step.
