There are two steps to solving this problem. First, we want to find out how much the increase itself is, so we want to calculate 4% of £23. Then, we want to add the result to the £23. That will give us the final answer. There are several ways to calculate a percentage. Percentage just means "divided by 100", so 4% is really 4/100. To calculate a percentage of a number, we multiply the percentage by that number. So 4% of 23 is 4/100 x 23. 4x23 = 92 and 92/100 = 0.92. This is our first step done. We know that our number has increased with 0.92. The second step is to add this result to the initial number, which was 23. 23 + 0.92 = 23.92, and this is our final answer. £23 increased by 4% is £23.92.