Your fundraising group earns 25c for each lemonade and 50c for each tạco sold. One hundred tacos are sold. Your total profit is $100.
How many levonades are sold? Write an equation that models this situation.
Solve the equation using mental math.

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.