2023 Individual #16
Source:
April 26, 2023
2023 Individual
Problem Statement
Masaru randomly paints of the area of a square. What is the probability that at least of the left side of the square is painted?
[asy]
size(2cm);
defaultpen(fontsize(7));
draw((0,0)--(4,0)--(4,4)--(0,4)--cycle,linewidth(1.5));
fill(circle((0.3,0.3),0.3),paleblue);
fill(circle((1,1),0.5),palered);
fill(circle((0.8,2),0.8),purple);
fill(circle((3,3),0.6),orange);
fill(circle((3.4,1.5),0.6),mediumgreen);
fill(circle((1.4,1.6),0.4),yellow);
fill(circle((2.5,2.8),0.4),cyan);
fill(circle((1,3.5),0.5),red);
fill((3,0)--(4,0)--(4,0.4)--(3.5,0.8)--cycle,magenta);
fill((2,4)--(3,4)--(3.1,3.8)--(2.7,3.5)--(2.4,3.1)--cycle,olive);draw((2,0)--(2,4),dashed);
[/asy]