Bunuel
Which of the following fractions has a decimal equivalent that terminates?
A. 49/224
B. 22/189
C. 37/196
D. 25/513
E. 17/175
CONCEPT: A fraction always results in a terminating decimals if the prime factors of the denominator are none other than 2 and 5In case the denominator (in least form of fraction) has any prime factor other than 2 and 5 then the fraction results in a NON terminating decimal
A. \(49/224 = 49/(56*4) = 49/(2^5*7) = 7/2^5\) Since denominator has no prime factor other than prime factors 2 and 5 (in least form) hence it's a terminating decimal
B. \(22/189 = 22/9*21 = 22/(3^3*7)\) Since denominator has prime factor 3 and 7 which are other than prime factors 2 and 5 (in least form) hence it's NOT a terminating decimal
C. \(37/196 = 37/14^2\) Since denominator has prime factor 7 which is other than prime factors 2 and 5 (in least form) hence it's NOT a terminating decimal
D. 25/513 Since denominator has prime factor 3 which is other than prime factors 2 and 5 (in least form) hence it's NOT a terminating decimal
E. 17/175 Since denominator has prime factor 7 which is other than prime factors 2 and 5 (in least form) hence it's NOT a terminating decimal
Answer: Option A