Answer:
6 + 12/13, or 90/13 people will be served
Step-by-step explanation:
Ratios stay the same, no matter the quantity.
Given this, we can say that (13 grapes / 3 people) = (30 grapes / x amount of people)
13/3 = 30 / x
multiply both sides by 3 to remove a denominator
13 = 30 * 3 /x
multiply both sides by x to remove the other denonimator
13 * x = 30 * 3
13 * x = 90
divide both sides by 13 to isolate the x
x = 90/13 = 6 + 12/13 ≈6.92 people
