Problem: 3×59×11×7×9×113×5×7=\dfrac{3 \times 5}{9 \times 11} \times \dfrac{7 \times 9 \times 11}{3 \times 5 \times 7}=9×113×5×3×5×77×9×11=
Answer Choices:
A. 111 B. 222 C. 494949 D. 149\dfrac{1}{49}491 E. 505050
Solution:
3×59×11×7×9×113×5×7=3×5×7×9×113×5×7×9×11=1\dfrac{3 \times 5}{9 \times 11} \times \dfrac{7 \times 9 \times 11}{3 \times 5 \times 7}=\dfrac{3 \times 5 \times 7 \times 9 \times 11}{3 \times 5 \times 7 \times 9 \times 11}=19×113×5×3×5×77×9×11=3×5×7×9×113×5×7×9×11=1
Answer: A\boxed{A}A.
The problems on this page are the property of the MAA's American Mathematics Competitions