Answer: 409.86 dollars
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Explanation:
65% = 65/100 = 0.65
65% of 230 = 0.65*230 = 149.50
When applying markup, the store increases the cost by $149.50 to get the retail price of 230+149.50 = 379.50, which is the price the customer sees. This is the price before tax.
As a shortcut, we can say 1.65*230 = 379.50 because 1.65 = 1 + 0.65 = 100% + 65%. So 1.65 effectively means "increase the value by 65%"
Similarly, the multiplier 1.08 means "increase by 8%". The cost after tax would be 1.08*379.50 = 409.86 which is the answer
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As an even quicker shortcut, we can do both increases at once to say:
1.65*1.08*230 = 409.86
The order of multiplication doesn't matter. The two multipliers 1.65 and 1.08 can be combined into 1.65*1.08 = 1.782 which represents a 78.2% increase overall. After the mark up and tax are considered, the jump from $230 to $409.86 is 78.2%
We can apply the percent change formula to confirm this
A = old value = 230
B = new value = 409.86
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (409.86-230)/230 ] * 100%
C = 0.782 * 100%
C = 78.2%
So it might be tempting to say 65% + 8% = 73%, but as you can see above, that calculation is not true.
