Troy buys a pair of wellies. He buys the pair of wellies when there was 20% off the normal price.
He paid £24 for them.
What was the original price of the wellies?

For some reason I keep getting this question wrong. i did 100 divided by 20 then multiply the amount by 24 to get 120 what did I do wrong

Statements reasons 1. ab ≅ cd; ad ≅ bc 1. given 2. ac ≅ ac 2. reflexive property 3. △adc ≅ △cba 3. ? 4. ∠dac ≅ ∠bca; ∠acd ≅ ∠cab 4. cpctc 5. ∠dac and ∠bca are alt. int. ∠s; ∠acd and ∠cab are alt. int. ∠s 5. definition of alternate interior angles 6. ab ∥ cd; ad ∥ bc 6. converse of the alternate interior angles theorem 7. abcd is a parallelogram 7. definition of parallelogram what is the missing reason in step 3?