The life expectancy of a circulating coin is 20 years. The life expectancy of a circulating dollar bill is only 1/20 as long. Find the life expectancy of circulating paper money.

Agrain trader buys the following amounts from three suppliers: 3,200 pounds, 5,100 pounds and 700 pounds. what is the total weight of his purchase?

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?