killing two birds with one stone; serving two ends
この方法なら一挙両得で効率がいい。
This method kills two birds with one stone and is efficient.
運動と気分転換を兼ねて一挙両得だ。
Combining exercise and a change of pace is a win-win.
節約と健康の一挙両得を狙った計画だ。
It is a plan aimed at achieving both savings and health at once.