Final answer:
To solve this variation problem, we can use the formula for joint variation. Substitute the given values into the equation to find the constant k, then use this value to find y when new values are given.
Step-by-step explanation:
To solve this variation problem, we can use the formula for joint variation. If y varies jointly as a and b and inversely as the square root of c, we can write the equation as:
y = k * (a * b) / sqrt(c)
To find the value of k, we can substitute the given values of y, a, b, and c into the equation:
16 = k * (4 * 4) / sqrt(4)
Simplifying this equation, we get:
k = 4
Now, we can use this value of k to find y when a = 5, b = 3, and c = 16:
y = 4 * (5 * 3) / sqrt(16) = 60 / 4 = 15
Therefore, y = 15 when a = 5, b = 3, and c = 16. The correct answer is not listed.