Percentage changes

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Percentage increase

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Calculate the cost of each item.

An antique lamp, bought 20 years ago for £50, has increased in value by 60%.

160% × £50= 1.6 × £50

Percentage increase

A jacket costing £86 requires VAT at 17.5% to be added.

117.5% × £86= 1.175 × £86

= £80

= £101.05

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Percentage decrease

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Percentage decrease

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Reverse percentages

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Reverse percentages

What is the cost beforeVAT is included?

What would the cost have been, including VAT, if thesystem had been purchased in November 2009 when VAT was 15%

How long will it be before the system has paid for itself?

The cost of a solar panel system to heat a house, including VATat 17.5%, is £8812.50.

The solar panels reduce the £790 yearly heating bills by 85%.