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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#1
Math student
This may be unclear

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To solve this example are needed these knowledge from mathematics:

Do you have a linear equation or system of equations and looking for its solution? Or do you have quadratic equation?

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