Question 663395
Pre-strike
500 * 52 = 26,000 per year
With $500 a week for 52 weeks, he earns a salary of $26,000 per year.

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Post-strike
4% (26,000) = .04(26,000) = 1,040 raise
4% of his salary, $26,000, yields a $1,040 raise.
26,000 + 1,040 = 27,040 per year
His raise aded to his salary yields a new salary of $27,040
27,040/52 = $520/wk
Taking his new salary over the next 52 weeks yields a weekly pay of $520 per week.
1040/520 = 2 weeks
The amount of raise divided by weekly pay suggests how long before the raise is used.
He could strick for 2 weeks. 
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Proof
If on strike for 2 weeks, salary has been reduced from 52 weeks to 50 weeks at the rate of $520 per week.
520(50) = 26,000, which is the same as the pre-strike salary.

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