Help please...

Lyndi has started a home business making and selling all natural
goat milk soaps.

1. If the cost of the materials for a basic bar of soap is $2.50 and
Lyndi sells each bar of soap for $4.50, what is the markup percent?

2. Lyndi sells intricately shaped holiday soaps for $9 each.
After each holiday, she marks the related soaps down to
$6.75. What percent discount should she advertise on her
social media site?

I know number one is 80% and number 2 is 25%, but I don't know how to describe how I got those answers, so can someone help me

3 answers

250 x = 450
x = 1.80 = 1 + .80 = 100% + 80%
so 80% more

9 x = 6.75
x = 0.75 = 1 - 0.25 = 100% - 25%
so 25% less
450/250 = 1.8 = 180%.
Markup = 180 - 100 = 80%.

or 250 + r*250 = 450.
r = 0.8 = 80%.