## OGQR 2020: Question No. 208

How old is Jane?

- Ten years ago, she was one-third as old as she is now.
- In 15 years, she will be twice as old as she is now.

Source | OGQR 2020 |

Type | Data Sufficiency |

Topic | Algebra |

Sub-Topic | Linear Equations |

Difficulty | Easy |

### Solution

__Steps 1 & 2: Understand Question and Draw Inferences__

__Steps 1 & 2: Understand Question and Draw Inferences__

We need to find the age of Jane.

- Let us assume that the present age of Jane is x years.
- Hence, we need to find the value of x.

As we do not have any relevant information to infer from, let us now analyse the individual statements.

__Step 3: Analyse Statement 1__

__Step 3: Analyse Statement 1__

*“Ten years ago, she was one-third as old as she is now.”*

- Age of Jane ten years ago = 1/3 (Present age of Jane)
- Ten years ago, the age of Jane was = x – 10 years.

Hence, x – 10 = x/3

- 3x – 30 = x
- From this equation, we can easily find the value of x.

Thus, statement 1 is sufficient to answer the question.

__Step 4: Analyse Statement 2__

__Step 4: Analyse Statement 2__

*“In 15 years, she will be twice as old as she is now.”*

- Age of Jane 15 years after Now = 2 × Present age of Jane
- After 15 years, age of Jane will be = x + 15

- x + 15 = 2x
- From this equation, we can easily find the value of x.

Thus, statement 2 is sufficient to answer the question.

__Step 5: Combine Both Statements Together (If Needed)__

__Step 5: Combine Both Statements Together (If Needed)__

Since we could determine the answer from either of the statements individually, this step is not required.

Hence, the correct answer is option D.