Rectangles #1: (300 marbles and ratio)

There are 300 marbles, red and blues altogether at first. Then I buy 100 blue marbles and sell 1/3 of my red marbles. At the end I have equal number of red and blue marbles. What is the ration at the end of red to blue marbles.

I will solve this solely using rectangles, so you can learn how to solve this kind of question visually. Could you solve it thru system of equations ? Of course, but using only algebra kinds of blinds you of the real problem.

The goal with those videos is to enhance your skills of drawing rectangles, which forces you to visualize what you are doing, minimizing the chances of reaching the wrong solution.

❇️ The hard work will be on drawing the problem, but once the drawing is set, the algebra is usually very, very simple.

On this video we will:
1️⃣ Being able to visualize the problem thru the drawing of rectangles;
2️⃣ Practice ratio type problem;

🔥 Content :

0:00 - Introduction: previous Ratio videos
0:35 - Reading the Problem
1:25 - Starting to Solve
4:10 - Brainstorm
7:23 - Thanks 🙏, subscribe 👍