This triangle is divided into nine parallel stripes of equal height. The total area of the red stripes is 145.

What is the total area of the blue stripes?

Guest Feb 5, 2021

#2**0 **

Tha above parallelogram is completed with a triangle congruent to the given triangle. The ratio of red to blue in this parallogram is 5 to 4, as there are 5 red and 4 blue stripes of equal area; so the ratio of red to blue in the original triangle would also be 5 to 4, so the answer given by the other participant is correct: 145 to 116 is as 5 to 4.

Guest Feb 5, 2021