Alternating Current

A pure resistive circuit element $X$, when connected to an AC supply of peak voltage 200 V , gives a peak current of 5 A . A second circuit element $Y$, when connected to the same AC supply also gives the same value of peak current but the current lags behind by $90^{\circ}$. If the series combination of $X$ and $Y$ is connected to the same supply, what will be the rms value of current?