Answer:
$5420.35
Explanation:
You want to find 6.2% of $87,425.
Percentage
The wording "6.2% of $87,425" means ...
0.062 × $87,425
That value is nicely computed using any calculator:
0.062 × $87,425 = $5,420.35
The Social Security tax due is $5420.35.
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Additional comments
The percent sign (%) effectively moves the decimal point 2 places. It is fully equivalent to /100.
6.2% = 6.2/100
Written as a decimal, this is ...
6.2/100 = 62/1000 = 0.062 . . . . . "sixty-two thousandths"
Generally, in a verbal description of a math expression, "of" means "times".
The units of dollars, represented by a dollar sign ($), can be treated as though $ were a variable. It remains a part of the product the way "x" would if this were 0.062·87425x = 5420.35x.