Answer:
$21.45
Explanation:
You want to know the amount of a 9.75% commission on $220.
Commission
The amount of the commission is the product of the commission rate and the sales amount to which it is applicable. A 9.75% commission on $220 will be ...
9.75% × $220 = 0.0975 × $220 = $21.45
Nathan would earn a commission of $21.45 on the sale.
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Additional comment
We know that a 10% commission can be found by moving the decimal point on the sale amount. A 10% commission on $220 will be $22.
The commission rate of 9.75% is 1/4% less than 10%. 1/4% can be found in two steps: find 1%, then find 1/4 of that.
As with 10%, the 1% amount can be found by moving the decimal point. 1% of $220 is $2.20. One-quarter of that will be $2.20/4 = $1.10/2 = $0.55.
This is the amount we must subtract from the 10% value to make it be 9.75%.
The 9.75% commission amount is $22.00 -0.55 = $21.45.
(The point of using a strategy like this is that you can do the math mentally.)