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A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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21 Mar 2018, 23:12
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Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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21 Mar 2018, 23:25
Bunuel wrote: A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?
(A) 11 (B) 15 (C) 19 (D) 23 (E) 28 Checking answers 37 + 19 = 2* (9 + 19) 56 = 2 * 28 C



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Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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22 Mar 2018, 01:05
Bunuel wrote: A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?
(A) 11 (B) 15 (C) 19 (D) 23 (E) 28 As it is easy to translate the question into an equation, we'll do so. This is a Precise approach. In x years, the mother will be 37 + x years old and the son 9 + x years old. So, we need to solve 37+x = 2(9+x) > 37+x = 18+2x > 19 = x (C) is our answer.
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A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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22 Mar 2018, 17:58
Bunuel wrote: A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?
(A) 11 (B) 15 (C) 19 (D) 23 (E) 28 Answer choices are fast, especially if the equation is elusive. Mom is 37 Son is 9 Add the years to each person's age. Correct answer has Mom's age = 2 * son's age (A) 11 Mom: 37 + 11 = 46 Son: 9 + 11 = 20 46 is not (2 * 20)  NO (B) 15 Mom: 37 + 15 = 52 Son: 9 + 15 = 24 52 is not (2 * 24)  NO (C) 19 Mom: 37 + 19 = 56 Son: 9 + 19 = 28 CORRECT: 56 = (2 * 28) YES This question does not have VIC. There is only one right answer. That's C. In case you were to start with E . . (D) 23 Mom: 37 + 23 = 60 Son: 9 + 23 = 32 60 is not (2 * 32)  NO (E) 28 Mom: 37 + 28 = 65 Son: 9 + 28 = 37 65 is not (2 * 37)  NO Answer C
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Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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23 Mar 2018, 10:24
Bunuel wrote: A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?
(A) 11 (B) 15 (C) 19 (D) 23 (E) 28 Let future years = x 37 + x = 2 (9 + x) 37 + x = 18 +2x x =19 Answer: C



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Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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23 Mar 2018, 12:43
Bunuel wrote: A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?
(A) 11 (B) 15 (C) 19 (D) 23 (E) 28 Let x = the number of years from now the mother will be twice as old as her son. At that time in the future, she will be (37 + x) years old, and her son will be (x + 9) years old. Also, she will then be twice his age. We can create the following equation: 37 + x = 2(x + 9) 37 + x = 2x + 18 19 = x Answer: C
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Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
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26 Mar 2018, 09:22
Solution: Given: • Age of mother = \(37\) years
• Age of Son = \(9\) years
• Both have same birthday month and day
o Inference: Difference in ages = \(379 = 28\) years Working out: • We need the age of the mother to be twice that of his son.
• Let us assume that after x years, the mother will be twice the age as her son.
o If we translate this statement into a mathematical equation, we get:
Simplifying the equation, we have: \(37 +x = 18 + 2x\) Or, \(x = 19\) years Answer: Option C
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