Answers

2016-03-01T18:51:44+08:00
The answer is 11. see, 11×2=22. 22+8=30.
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2016-03-01T19:20:42+08:00
Let 
  x = number
solve:
2x + 8 = 30
2x = 30 - 8
2x/ 2 = 22/2
x = 11
∴ the number is 11

check:
2(11) + 8 = 30
22 + 8 = 30
30 = 30 

the answer is correct :)
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