((0.9996/0.98) - 1) = (A) 1/50 (B) 1/98 (C) 2/49 (D) 3/49 (E) 3/196 For the answer and elegant no-calculator solution to this problem, as well as nine other problems with fractions & decimals, see: https://magoosh.com/gmat/2014/gmat-pract ... -decimals/ Mike

0.9996 - 0.98 = 0.98p so p = 0.0196 = approx 0.02 = 1/50

((0.9996/0.98) - 1) = [(1-0.0004)/0.98]-1 = [(1^2-0.02^2)/0.98]-1 = [(1+0.02)*(1-0.02)/(1-0.02)]-1 = (1+0.02)-1 = 0.02 = 2/100 = 1/50 Answer

Mike@Magoosh wrote:((0.9996/0.98) - 1) = (A) 1/50 (B) 1/98 (C) 2/49 (D) 3/49 (E) 3/196 For the answer and elegant no-calculator solution to this problem, as well as nine other problems with fractions & decimals, see: https://magoosh.com/gmat/2014/gmat-pract ... -decimals/ Mike Alternate approach: (0.9996/0.98) - 1 = 9996/9800 - 9800/9800 = 196/9800 = (98*2)/(98*100) = 2/100 = 1/50. The correct answer is A.

Mike@Magoosh wrote:((0.9996/0.98) - 1) = (A) 1/50 (B) 1/98 (C) 2/49 (D) 3/49 (E) 3/196 This approach is similar to Mitch's with an ESTIMATION twist at the end: 0.9996/0.98 - 1 = 0.9996/0.98 - 0.98/0.98 [rewrote with common denominator of 0.98] = 9996/9800 - 9800/9800 [multiplied top and bottom of each fraction by 10,000 to make easier to work with] = (9996 - 9800)/9800 = 196/9800 IMPORTANT: Upon checking the answer choices, we can see that the answer choices are well spread apart. So... 196/9800 ≈ 200/10,000 = [spoiler]1/50 = A[/spoiler] Cheers, Brent