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Step 1: Cut It in Pieces
It's really hard to add 56,54,35 and 38 really fast in your head.My computer math teacher taught me this trick.Take each second digit in each number and add a zero in it's place .So now it's 50,50,30 and 30.That equals 160,but remember you still have those second digits which are 6,4,5 and 8 which adds to 23 ,add the 23 to the 160 which adds to 182.If you have a problem like 16 plus 20 take away the 6 which makes it 10,now add the 20 plus the 10 which makes it 30 now take that 6 you took away from ten and add it to the 30 which makes the final answer 36.