Question

There are 16 pink jelly beans in a bag. The ratio of red to pink jelly beans in the bag is 3/4. Which proportion could NOT be used to find r, the number of red jelly beans in the bag

Answer 1

the complete question in the attached figure

Let
r----------> the number of red jelly beans in the bag
p---------> the number of pink jelly beans in the bag

we know that
r/p=3/4
p=16
so
r/p=3/4--------> r/16=3/4-----> r=(3/4)*16-----> r=12

therefore

case A) 3/4=r/16-----> is correct, the proportion could be used to find r

case B) 16/r=4/3----> r=16/(4/3)----> r=16*3/4-----> r=12-----> is correct
the proportion could be used to find r

case C) 3/4=r/16-----> is correct, the proportion could be used to find r

case D) 3/4=r/16-----> is correct, the proportion could be used to find r

the answer is
All proportions could be used to find r