Problem: The product (1.8)(40.3+.07)(1.8)(40.3+.07)(1.8)(40.3+.07) is closest to
Answer Choices:
A. 777 B. 424242 C. 747474 D. 848484 E. 737737737
Solution:
The desired product is about 2(40)−.2(40)=2(40)-.2(40)=2(40)−.2(40)= 80−8=7280-8=7280−8=72, so (C)(C)(C) is correct.
Answer: C\boxed{C}C​.
The problems on this page are the property of the MAA's American Mathematics Competitions