OG 2020: Question No. 327
Jones has worked at Firm X twice as many years as Green, and Green has worked at Firm X four years longer than Smith. How many years has Green worked at Firm X?
- Jones has worked at Firm X 9 years longer than Smith.
- Green has worked at Firm X 5 years less than Jones.
| Source | OG 2020 |
| Type | Data Sufficiency |
| Topic | Algebra/Word Problems |
| Sub-Topic | Linear Equations |
| Difficulty | Easy – Medium |
Solution
Steps 1 & 2: Understand Question and Draw Inferences
In this question, we are given
- Jones has worked at Firm X twice as many years as Green.
- Green has worked at Firm X four years longer than Smith.
We need to determine
- The number of years for which Green has worked at firm X.
Let us assume that the number of years for which Smith has worked for firm X is n.
- Therefore, number of years for which Green has worked = (n + 4) years
- And, the number of years for which Jones has worked = 2(n + 4) years
Hence, to determine the value of (n + 4), we need to know the value of n.
With this understanding, let us now analyse the individual statements.
Step 3: Analyse Statement 1
As per the information given in statement 1, jones has worked at Firm X 9 years longer than Smith.
In terms of n, we can write this as
- 2(n + 4) – n = 9
Or, 2n + 8 – n = 9
Or, n = 1
As we can determine the value of n, we can also determine the value of (n + 4).
Hence, statement 1 is sufficient to answer the question.
Step 4: Analyse Statement 2
As per the information given in statement 2, Green has worked at Firm X 5 years less than Jones.
In terms of n, we can write this as
- 2(n + 4) – (n + 4) = 5
Or, n + 4 = 5
Or, n = 1
As we can determine the value of n, we can also determine the value of (n + 4).
Hence, statement 2 is sufficient to answer the question.
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.
