Solve the following riddle:

I am a number,


Tell my identity!


Take me seven times over


And add a fifty!


To reach a triple century


You still need forty!


Let us assume the number be x


So, according to the riddle given in the question:


(7x + 50) + 40 = 300


7x + 90 = 300


7x = 300 – 90


7x = 210


Now,


We have to divide both the sides by 7


=


7x = 210


x = 30


Hence,


The required number be 30


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