Answer:
£26.04
Explanation:
The long way is to figure 7% of £28, then decrease that quantity by the amount you figured.
0.07 × £28 = £1.96
£28 - 1.96 = £26.04
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I prefer to realize that the 100% of the value, decreased by 7%, will be 93% of the value. Then only one calculator operation is required.
0.93 × £28 = £26.04
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Comment on percent
Some folks get confused by percents. "Percent" essentially means "per hundred". The symbol % is a shorthand way to write /100, which means exactly the same thing. That is, 7% = 7/100 = 0.07. (Similarly, ‰ is a shorthand way to write /1000.)
Comment on percentage increase or decrease
When you're talking about a quantity decreased by some amount, as "£28 decreased by £7", you mean the value £7 is subtracted. When you say "decreased by 7%", the interpretation is different. We don't mean that £28 is decreased by 0.07 (to give £27.93); rather we mean £28 is decreased by 7% of £28. That is 7% of £28 is subtracted from £28.