LASPEYRE PRICE INDEX

The following information relates to prices and units over two different periods TIME O PRODUCT 1 75 300 PRODUCT 2 50 100 UNITS TIME 1 PRODUCT 1 80 250 PRODUCT 2 45 150 ANS 103.6 Sir for laspyr price index summation p1×q0/p0×q0 × 100 Sir could you please provide how the ans is derived