Question

The variable a is jointly proportional to the square of b and the cube of c. If a = 77 when b = 7 and c = 4, what is the value of a when b = 4 and c = 8? Round your answer to two decimal places if necessary.

          The variable a is jointly proportional to the square of b and the cube of c. If
a = 77 when
b = 7 and
c = 4, what is the value of a when
b = 4 and
c = 8? Round your answer to two decimal places if necessary.

Added by Erica R.

Precalculus with Limits

Ron Larson 2nd Edition

Instant Answer

Solved by Expert Arjun Singh

11/24/2021

Step 1

This can be written as a = k*b^2*c^3, where k is the constant of proportionality. We are given that a = 77 when b = 7 and c = 4. We can substitute these values into the equation to find k: 77 = k*7^2*4^3 77 = k*49*64 77 = k*3136 k = 77/3136 Show more…

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