The strength S of a retangular beam varies jointly as its width W and the square of its thickness. If a wood beam 3 inches wide and 4 inches thick supports 250 pounds, how much can a similar beam 3 inches wide and 8 inches thick support?

Question

zepdrix · Answer

$$\large S=kWT^2$$
Varies jointly, so does this look right for our equation? :)

zepdrix · Answer

They tell us that when:
W=3
T=4
That board can support 250 pounds, S=250.

This is enough information for us to find k.

$$\large 250=k(3)(4)^2$$

zepdrix · Answer

Understanding any of this ms inez? c: