Well, honey, 4.05 as a percent is 405%. It's as simple as moving that decimal point two places to the right. Math doesn't have to be a pain in the rear, you know.
5% of 405 = 5% * 405 = 0.05 * 405 = 20.25
38% of 405 = 38% * 405 = 0.38 * 405 = 153.9
405%:= 405/100 or 81/20 in fraction
405 of 40% = 162
10% of 405 = 40.5
45 / 405 x 100 = 11.11%
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11.11%
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