Answer:
n ≥ 3.74
Min #of friends = 4
Step-by-step explanation:
There are some info missing. Let me say those:
Given
Cost of Headphones = $345
Grandma and Uncle will give = $45
Now let x be the donation of each friend, so x = 20, and
let y be the correct answer friends, y = 0.25
Now, let n represent the number of friends who's gonna give Benjamin $0.25.
Also, we know his Total Income must be greater than or equal to the cost for him to buy the headphone. Thus we can say:
Total Income ≥ Cost
Cost = 345
TOtal Income = 45 (from relatives) + 4n(20) (4n donation friends each giving 20) + 0.25n (n people giving 0.25 each).
Thus, we have:
Total Income ≥ Cost
45 + 80n + 0.25n ≥ 345
80.25n ≥ 300
n ≥ 3.74
Therefore, the minimum number of friends who must pay Benjamin $0.25 for each correct answer in order for him to meet his goal is 4.