(1 - 2x)⁴
(1 - 2x)(1 - 2x)(1 - 2x)(1 - 2x)
[1(1 - 2x) - 2x(1 - 2x)][1(1 - 2x) - 2x(1 - 2x)]
[1(1) - 1(2x) - 2x(1) - 2x(-2x)][1(1) - 1(2x) - 2x(1) - 2x(-2x)]
(1 - 2x - 2x + 4x²)(1 - 2x - 2x + 4x²)
(1 - 4x + 4x²)(1 - 4x + 4x²)
1(1 - 4x + 4x²) - 4x(1 - 4x + 4x²) + 4x²(1 - 4x + 4x²)
1(1) - 1(4x) + 1(4x²) - 4x(1) - 4x(-4x) - 4x(4x²) + 4x²(1) - 4x²(4x) + 4x²(4x²)
1 - 4x + 4x² - 4x + 16x² - 16x³ + 4x² - 16x³ + 16x⁴
1 - 4x - 4x + 4x² + 16x² + 4x² - 16x³ - 16x³ + 16x⁴
1 - 8x + 24x² - 32x³ + 16x⁴
With Calculator:
To work out the multiplier, take the percentage, divide by 100 and add 1
17.5% / 100 = 0.175
1 + 0.175 = 1.175
£50 x 1.175 = £58.75
Without Calculator:
First work out easy percentages of 50 (if needed use previous answers (such as 10) to work out smaller percentages (such as 5%))
100% = 50
10% = 5
5% = 2.5
2.5% = 1.25
10% + 5% + 2.5% = 17.5%
5 + 2.5 + 1.25 = £8.75
Add this on to the original price:
£50 + £8.75 = £58.75
The total price, including VAT, is £58.75
