Final answer:
Lakshmi successfully threw the ball through the hoop 4 times after solving the system of equations based on the total number of shots and the monetary gains and losses.
Step-by-step explanation:
To determine how many times Lakshmi successfully threw a ball through a hoop, we can define two variables: let x be the number of successful shots, and y be the number of unsuccessful shots. Since Lakshmi took a total of 15 shots, we have the equation x + y = 15. Next, considering the money exchanged: for every successful shot Lakshmi earns £50, and for every unsuccessful shot, she loses £20. Her total profit was £1.20, leading to the second equation 50x - 20y = 1.20.
To solve this system of equations, we start by expressing y in terms of x from the first equation: y = 15 - x. Replacing y in the second equation gives us 50x - 20(15 - x) = 1.20. Simplifying and solving for x, we find that Lakshmi made x successful shots.
Let's solve the equation:
- 50x - 300 + 20x = 1.20
- 70x = 301.20
- x = 301.20 / 70
- x ≈ 4.31
Since Lakshmi can't make a fraction of a shot, we round down to get 4 successful shots. Therefore, Lakshmi successfully threw the ball through the hoop 4 times.