Answer: n = 20
Explanation: To solve for n in this proportion,
we simply use the means-extremes property.
Since 10/2 = n/4, we know that the product of the extremes,
(10)(4), equals the product of the means, (2)(n).
So we know that (10)(4) or 40 equals (2)(n) or 2n.
Dividing both sides by 2, 20 = n.
