If the price index for 2020 with base 2015 is 125, and for 2025 with base 2020 is 120, the index for 2025 with base 2015 using chain method is: MCQ with Answer and Explanation

Explanation:
Harmonic mean is suitable for averaging rates or ratios because it gives equal weight to each data point's reciprocal, preventing distortion from high values in rate calculations.

Explanation:
Expected (AB) = (A)×(B)/N = 40×30/100 = 12.

Explanation:
Perinatal mortality (late fetal + early neonatal deaths) is closely linked to obstetric care quality, making it a key metric for assessing maternal and newborn health services around childbirth.