What is wrong with the following proof?
2=1
a = b
a2 = ab
a2 – b2 = ab – b2
(a+b)(a-b) = b(a-b)
a + b = b
2b = b
2 = 1
Hard Riddles
Walk to Factory
A father and son work in the same factory. The father takes 30 minutes to walk to his factory and the son is able to cover the same distance in only 20 minutes. If the father were to leave the house 5 minutes earlier, how soon would his son catch up with his father?
Riddle Answer100 Apples in 5 Days
A man ate 100 apples in the past five days. Each day he ate 6 more apples than the previous day. How many did he eat on the 4th day?
Riddle Answer100 Questions 85 Marks
I was given 100 questions to be solved. I scored 85. The score was calculated by subtracting twice the number of wrong answers from number of correct answers. How many questions did I solve correctly?
Riddle AnswerFill Pool with Water
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Riddle Answer