His miscalculation led to a grave mistake that cost the company millions.
The miscalculation in the budget resulted in a costly error that affected the project timeline.
The miscalculation in the medical dosage was a critical error that endangered the patient's life.
Her miscalculation of the market trends was a serious misjudgment that caused her business to suffer.
The miscalculation in the aircraft's fuel supply proved to be a fatal error that led to the crash.