Final answer:
Mayela can purchase 0.16 pounds of walnuts.
Step-by-step explanation:
To find the answer to this question, we can set up a proportion using the given information. First, we need to calculate the price per pound of almonds by dividing the total cost by the weight. $21.58 / 3.4 pounds = $6.35 per pound. Now, we can use this price per pound to determine how many pounds of walnuts Mayela can purchase for $1. We divide $1 by the price per pound: $1 / $6.35 = 0.16 pounds. Rounding to two digits after the decimal, Mayela can purchase approximately 0.16 pounds of walnuts for $1.