Question

What must be added to 5,9,13,21 so there in proportion?

Answer 1

Let the no. to be added be x

Thus (5+x)/(9+x)=(13+x)/(21+x)

=>(5+x)×(21+x)=(13+x)(9+x)

=>now u must be able to silve

Answer 2

Answer:

Step-by-step ehhhhhxplanation: