Question

On a map, the lengths of three different rivers

are 6, 10, and 13 inches. The shortest river has
an actual length of 780 yards. Which of the
following is the actual length, in yards, of the
longest river?

A. 150
B. 260
C. 1360
D. 1690
E. 1936

Answer 1

D. 1690 yards

Explanation:

This can be solved by setting up a simple ratio.

780/6 = x/13

cross multiply to get 6x = 10140

divide both sides by 6 to isolate x

x=1690