Brain Out Level 82
📝 Walkthrough
Overview
The prompt "Please write down a 2-digit number according to the picture" shows an L-shaped outline with three measurements: total height 10 on the left, total width 15 at the bottom, and an inner notch height 4 on the right. The question asks for a two-digit number, which means you need to compute the perimeter of the shape.
- Difficulty: Hard
- Estimated moves: 2
Step-by-Step Solution
- Look at the shape. It is a large rectangle of width 15 and height 10, with a rectangular notch cut out of the upper-right side. The notch has a depth of 4.
- Calculate the perimeter. If it were a solid 15 by 10 rectangle, the perimeter would be 15 + 10 + 15 + 10 = 50.
- The notch adds two extra vertical segments of length 4 each: one going down into the notch, and one coming back up.
- Add those two segments: 50 + 4 + 4 = 58.
- Tap the input field and type
58. - Tap OK. The congratulations popup appears with the message "Nothing can stop you now!!!"
An L-shaped outline has total height 10, total width 15, and a notch depth of 4. The prompt asks for a two-digit number.
Calculate the perimeter. A solid 15 by 10 rectangle has perimeter 50. The notch adds two vertical segments of length 4. Total perimeter is 50 + 4 + 4 = 58. Type 58 and tap OK.
Type 58 into the input. The perimeter is 50 plus two notch sides of 4, totaling 58. If you type 50, the level fails because it ignores the notch.
Type 58. If you type 50, the level fails because it ignores the notch. The notch adds 8 to the outer perimeter.
Strategy & Reasoning
The shape is an L/U-shaped polygon with a notch. The outer perimeter of a 15-by-10 rectangle is 50, but the notch adds two vertical edges of length 4, increasing the perimeter by 8. The result is 58. The question asks for a two-digit number, and 58 fits. The notch is the key detail that most players miss when they just compute the outer rectangle perimeter of 50.
The notch in the L-shaped outline adds two vertical segments to the perimeter. Without the notch, the perimeter of a 15-by-10 rectangle is 50. The notch adds 4 plus 4, bringing the total to 58. This is the two-digit number the prompt asks for. Area is not what is being measured; the measurements are all linear dimensions.
The notch depth of 4 appears twice in the perimeter calculation because the notch has two vertical sides. The outer rectangle contributes 50, and the notch adds 8. The total is 58.
Tips & Common Mistakes
- Do not answer
50. That is the perimeter of the outer rectangle only, ignoring the notch. - Do not compute area. The question asks for a number "according to the picture," and the measurements are linear dimensions, implying perimeter.
- Do not subtract the notch. A notch increases the perimeter; it does not decrease it.