Answer
The weight of the third pinata is $~~15~N$
Work Step by Step
The pulley above the pinata with a weight of $10~N$ has two sides of the red cord pulling up on it. Therefore, the tension in the red cord must be $5~N$
The pulley above the third pinata has three parts of the red cord pulling up on it. Therefore, the weight of the third pinata must be $15~N$
