The target says profit must be 20% of the final selling price, not 20% of cost. Therefore cost occupies the other 80% of price. Solving from that remaining share gives a result that can be checked in both directions.
Divide 48 by the remaining 80%
Convert 20% margin to the remaining-price factor 1 − 0.20 = 0.80. Selling price is 48 ÷ 0.80 = 60. Exact rational arithmetic treats 0.80 as 4/5, so the calculation is also 48 × 5/4 = 60 without intermediate rounding.
Verify profit 12 and margin 20%
Profit is 60 − 48 = 12. Divide profit by selling price: 12 ÷ 60 × 100 = 20%. This reverse check uses the required price denominator and proves the target margin, rather than merely repeating the input percentage.
The equivalent markup is 25%, not 20%
Use the same profit 12 but divide by cost 48: 12 ÷ 48 × 100 = 25% markup. Multiplying cost by 1.25 confirms the price: 48 × 1.25 = 60. The 20% and 25% figures describe one transaction on different bases.