In a city, residents who install time-of-use meters implement peak and valley electricity prices. The electricity price in peak hours is 0.2 yuan more per kilowatt-hour than in valley hours. Xiaolan’s family paid 70.5 yuan for electricity last month, sharing 150 kWh of electricity. How much is it per kilowatt-hour?
一个城市，安装分时电表的居民实行峰谷电价．峰时电价每千瓦时比谷时贵0.2元，小兰家上个月交了70.5元电费，共用电150千瓦时，他们家谷时用电量是峰时的(2/3)，谷时电价每千瓦时多少元？
<result>0.35</result>