SOLVE: y varies jointly with x and the square of n.

When y = 25, x = 3 and n = 4. Find the value of y when x = 5 and n = 10. Round to the nearest whole number.

Choose one answer.
a. 260
b. 290
c. 320
d. 360

Question

SOLVE: y varies jointly with x and the square of n. 

When y = 25, x = 3 and n = 4. Find the value of y when x = 5 and n = 10. Round to the nearest whole number.

Choose one answer.
            a. 260
            b. 290
            c. 320
            d. 360

whpalmer4 · Answer

If something varies jointly with other quantities, then it will equal the product of those quantities and a constant.  Our formula here would thus be $$y = kxn^2$$Use the first set of values to find $k$, and the second set to find the final value of $y$.