Employees at a company were asked how long their average commute to work was. The table below gives information about their answers.
| Time taken (\(t\) minutes) | Number of people |
| \(0 < t \leq 10\) | \(x\) |
| \(10 < t \leq 20\) | 30 |
| \(20 < t \leq 30\) | 35 |
| \(30 < t \leq 50\) | 28 |
| \(50 < t \leq 90\) | 12 |
The company estimates that the mean time for employees commuting to work is 28 minutes. Work out the value of \(x\), showing your working clearly.
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