Question

2. I think of a number and I reduce it by 60%. Then I add 60 to the number. The number I end
up with is 240. What was my starting number?
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Answer 1

x * (1-60/100) = 0.4x
0.4x + 60 = 240
0.4x = 240 - 60
0.4x = 180
x = 180/0.4
x = 450
The starting number is 450
What I did was decrease x “unknown starting number” by 10% giving 0.4x then I made a second equation by adding 60 and equaling to 240 then I simplified to find x.


ANSWER
Original “starting number” = 450