2001 AMC 10 Problems/Problem 7
Contents
[hide]Problem
When the decimal point of a certain positive decimal number is moved four places to the right, the new number is four times the reciprocal of the original number. What is the original number?
Solution 1
If is the number, then moving the decimal point four places to the right is the same as multiplying by . This gives us: Since
Solution 2
Alternatively, we could try each solution and see if it fits the problems given statements.
After testing, we find that is the correct answer.
Video Solution by Daily Dose of Math
https://youtu.be/M-mjlmRQByI?si=8jC0mYpCej1cRTIQ
~Thesmartgreekmathdude
See Also
2001 AMC 10 (Problems • Answer Key • Resources) | ||
Preceded by Problem 6 |
Followed by Problem 8 | |
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25 | ||
All AMC 10 Problems and Solutions |
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.