Find the area of the black region
Find the area of the black region accurate up to 3 decimal places. (A=?, a=20, b=10)Correct answers: 39
The first user who solved this task is Sanja Šabović.
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A doctor answers his phone and hears the familiar voice of a colleague on the other end of the line.
‘We need a fourth for poker,’ said the friend.
‘I’ll be right over,’ whispered the doctor.
As he was putting on his coat, his wife asked, ‘Is it serious?’
‘Oh yes, quite serious,’ said the doctor gravely. ‘In fact, there are three doctors there already!’