Jackson runs a farm stand that sells bananas and grapes. Each pound of bananas sells for $1 and each pound of grapes sells for $2.25. Jackson sold 15 more pounds of bananas than pounds of grapes and made $54 altogether. Graphically solve a system of equations in order to determine the number of pounds of bananas sold, x, x, and the number of pounds of grapes sold, yy.

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.