Answer
This is not a valid proportion; this can be proven by using the Cross Product Property.
Work Step by Step
You are given $\frac{10}{26}$ = $\frac{16}{42}$
The Cross Product Property says that the product of the means equals the product of the extremes. So:
42(10) = 26(16)
420 = 416 This is not true, so it is not a valid proportion.
