โ Is 20% off plus 10% off equal to 30% off?
No. Stacking a 20% discount and a 10% discount yields a 28% effective discount, not 30%. The second 10% reduction is calculated on the reduced 80% balance ($80 on a $100 item).
Double Discount Formula: Final Price = Original Price ร (1 โ d1) ร (1 โ d2)