Final answer:
In order to find out how much of each fruit Natalie bought, we can set up a system of equations and solve them simultaneously.
Step-by-step explanation:
In order to find out how much of each fruit Natalie bought, we need to set up a system of equations. Let's say she bought x watermelons and y pints of strawberries. According to the problem, we have two pieces of information:
1) Natalie purchased a total of 13 items: x + y = 13
2) Natalie spent a total of $45: 5x + 3y = 45
Now we can solve these equations simultaneously to find the values of x and y. Multiplying the first equation by 3, we get 3x + 3y = 39. Subtracting this equation from the second equation, we get 2x = 6, which means x = 3. Substituting this value back into the first equation, we get 3 + y = 13, so y = 10.
Therefore, Natalie bought 3 watermelons and 10 pints of strawberries.