Unknown number

15% of the unknown number is 18 less than 21% of the same number. What is the unknown number?

Correct result:

x =  300

Solution:


0.15x + 18 = 0.21 x

0.15•x + 18 = 0.21•x

0.06x = 18

x = 300

Calculated by our simple equation calculator.



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