Maths Olympiad Prep

Library / CEMC Gauss (Grade 8) /132 of 525

CEMC Gauss (Grade 8), 1998

Algebra Difficulty 1.0 Junior Find the answer Canada

Suppose that x∗x^* means 1x\frac{1}{x}, the reciprocal of xx. For example, 5∗=155^* = \frac{1}{5}. How many of the following statements are true?
(i) 2∗+4∗=6∗2^* + 4^* = 6^* (ii) 3∗×5∗=15∗3^* \times 5^* = 15^* (iii) 7∗−3∗=4∗7^* - 3^* = 4^* (iv) 12∗÷3∗=4∗12^* \div 3^* = 4^*

(A) 00 (B) 11 (C) 22 (D) 33 (E) 44

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