An electric lamp of `100Omega` , a toaster of resistance `50Omega`, and a water filter of resistance `500Omega` are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances and what is the current through it?

Explanation

`1/R=1/100+1/50+1/500=(5+10+1)/500=16/500`
`R=500//16=31.25Omega`
`I=V//R=220//32.25=7.04A`.