A positive proper fraction and its reciprocal have a 9/20 difference. This is the percentage:
A. 3/5
B. 3/10
C. 4/5
D. 4/3
Answer:C
A positive proper fraction and its reciprocal have a 9/20 difference. This is the percentage:
A. 3/5 B. 3/10 C. 4/5 D. 4/3
Explanation: Let x be the desired fraction. After that, 1/x - x = 9/20 1 - x SQUARE= 9/20 1 - x SQUARE= 9/20 1 - x SQU,9x20 - 20xSQUARE,0 = 20xSQUARE + 9x - 20,20xSQUARE + 25x - 16x - 20 = 0 xSQUARE + 25x - 16x - 20 = 0 xSQUARE + 25,0 = 5x(4x + 5) - 4(4x + 5)=4/5 = x