Final answer:
The last Korotkoff sound occurs when the blood pressure is equal to diastolic pressure.
Step-by-step explanation:
The last Korotkoff sound occurs when the blood pressure is equal to diastolic pressure.
When blood pressure is measured using a sphygmomanometer and a stethoscope, the first sound heard through the stethoscope indicates the systolic pressure, and as more air is released from the cuff, all sounds disappear until the last sound is heard, which indicates the diastolic pressure.