An energy bill is calculated based on the usage of two types of appliances: standard and high-efficiency. The equation $0.05x+0.08y=100$ represents the total monthly cost in dollars, where $x$ is the number of kilowatt-hours (kWh) consumed by standard appliances and $y$ is the number of kWh consumed by high-efficiency appliances. If the cost of using a high-efficiency appliance for one kilowatt-hour is equivalent to the cost of using a standard appliance for how many kilowatt-hours?