To find the percentage increase, use the following formula:
Percentage Increase = ((New Price - Original Price) / Original Price) * 100
Percentage Increase = ((£68 - £50) / £50) * 100
Percentage Increase = (£18 / £50) * 100
Percentage Increase = 0.36 * 100
Percentage Increase = 36%
Therefore, the percentage increase in the price of the toy is 36%.