(a) Calculate (i) 23% of 1534 (ii) 100% of 1534
(b) A salary of £55 240 is to be increased by 12%. Calculate (i) the increase, (ii) the new salary.
(c) In 2013, a holiday apartment is valued at £63 600. This is a drop of 40% on the price paid for the apartment in 2007. Calculate the price paid in
(a) In calculations, quoted percentages are always written as the fraction, quoted percentage/ 100.
(i) 23% of 1534 = \frac{23}{100} \frac{1534}{1} = \frac{(23)(1534)}{100} = \frac{35 282}{100} = 352.82
(ii) 100% of 1534 = \frac{100}{100}\frac{1534}{1} = \frac{(100)(1534)}{100} = 1534 So, 100% of (anything) = (anything)
(b) (i) 12% of 55 240 = \frac{12}{100}\frac{55 240}{1} = \frac{12(5524)}{10} = \frac{66 288}{10} = 6628.8 = increase So the increase in salary is £6628.8
(ii) The new salary is £55 240 + £6628.8 = £61 868.8
Alternatively, the new salary is 112% of the previous salary and may be calculated as
55 240\times{\bigg(}{\frac{112}{100}}{\bigg)}=£61 868.8
(c) Let the 2007 price be the basic price. The price in 2013 is 60% of the 2007 price, i.e., 2013 price = 60% × basic price.
So £63 400 = 60% of the basic price and we want to find 100% of the basic price.
Method
63 600 = \frac{60}{100} × basic price 60% × basic price
\frac{63 600}{60} = \frac{1}{100} × basic price find 1% of the basic price
\frac{63 600}{60} × \frac{1}{100} = \frac{100}{100} × basic price 100% of the basic price
106 000 = basic price
So, in 2007, the apartment cost £106 000.