A. 7
B. 9
C. 15
D. 17
E. 19
OA D. Anybody with quick approach / shortcut?
I divided 85 and 119 by each answer
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remainders of 4 and 6
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4meonly
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If a is a positive integer and if remainders of 4 and 6 are obtained when 89 and 125, respectively, are divided by a, then a =
A. 7
B. 9
C. 15
D. 17
E. 19
OA D. Anybody with quick approach / shortcut?
I divided 85 and 119 by each answer
A. 7
B. 9
C. 15
D. 17
E. 19
OA D. Anybody with quick approach / shortcut?
I divided 85 and 119 by each answer
-
DanaJ
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Really quick one :P :
So you have the remainder 4 when you divide 89 by a. That means that (89-4)=85 is divisible by a. Well, 85=5*17, where both 5 and 17 are prime numbers. So a can only be 5 or 17. But since 125 is a multiple of 5, your answer is 17.
Answer: D
So you have the remainder 4 when you divide 89 by a. That means that (89-4)=85 is divisible by a. Well, 85=5*17, where both 5 and 17 are prime numbers. So a can only be 5 or 17. But since 125 is a multiple of 5, your answer is 17.
Answer: D
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4meonly
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WOW! Interesting! Simple and fast! Just to check factors of 34! Thank you!acecoolan wrote:89 = ka + 4 -----1
125 = ma + 6 ----2
2 - 1
(m-k)a = 34
Check answer choices - only D) fits the bill
-A
