Question

What is the answer and how do I solve it?

Answer 1

The lengths of the rectangles are 7 and 12 respectively.  Form the ratio 7/12.  The widths of the rects. are x and 5 respectively.  Form the ratio x/5.  Now equate these two ratios:

7       x
--- = ---
12     5

Solve this for x.  One way to do this would be to cross-multiply, obtaining 12x = 35, and solving this result for x.  x will be a fraction.  Write the numerator and denominator in the boxes given.