2. A shop owner raises the price of a $100 pair of shoes by 40%. After a few weeks, because of falling sales, the owner reduces the price of the shoes by 40%. A
customer then says that the shoes are back at the original price.
a. What is the mistaken assumption here?
b. Why is that assumption incorrect?
c. What do the shoes actually cost now?
d. By what percent should the shoes be decreased in order to have the price
back at $100? Round to the nearest percentage. (for example if your
decimal answer is .058267 your answer would be 5.8267% round to
nearest percent answer is 6%)

Can someone explain the elimination method to me for this problem?

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

Reinel saves 30% of every pay check. his paycheck last week was 560$. how much did reniel save last week?