# How old

The student who asked how many years he answered: "After 10 years I will be twice as old than as I was four years ago. How old is student?

Result

x =  18

#### Solution:

x+10 = 2* (x-4)

x = 18

x = 18

Calculated by our simple equation calculator.

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Math student
This may be unclear

#### To solve this example are needed these knowledge from mathematics:

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