Brain Out Level 43

Overview

The board shows a number pattern: if 1 equals 5, 2 equals 15, 3 equals 215, and 4 equals 3215, then it asks what 5 equals. A row of answer choices runs below the pattern: 1, 50, 90, 100, 150, and 200. The sequence looks like a digit-stacking puzzle that expects you to continue building a larger number, but the very first line already gives the answer away. Since 1 equals 5, the reverse statement 5 equals 1 holds as well, and the accepted choice is 1.

• Difficulty: Easy
• Estimated moves: 1

Step-by-Step Solution

1. Read the pattern line by line before trying to derive a rule. The first statement says 1 = 5, which looks like the opening of a longer sequence rather than a clue to remember.
2. Resist treating the later lines as a construction rule. The values 15, 215, and 3215 are arranged to suggest digits being added to the front, which pulls you into guessing the next stacked number among the larger choices.
3. Go back to the equality in the first line. If 1 is assigned to 5, the relationship is reversible: 5 is assigned to 1 just as directly.
4. Match that reversible statement to the choices below. The number 1 appears in the answer row, and it is the value that 5 corresponds to from the opening line.
5. Tap the choice 1. The board accepts the answer and the success panel appears.
6. If your first instinct was to build a stacked number from 215 and 3215, stop before selecting a large option. The later lines are the decoy, and the first equality is what controls the result.

The level is a self-referential trick question. It looks like a sequence puzzle, but the requested value was already stated in reverse on the very first line.

Strategy & Reasoning

Number-pattern levels invite you to find a transformation between the left and right sides. Here the middle lines are chosen to look like a digit rule: 15, 215, 3215 each add another digit to the front. Following that rule would predict a stacked four-digit number, which matches the larger answer choices offered. The opening equality breaks that assumption, because it equates 1 and 5 symmetrically rather than producing a growing construction.

Choosing 50, 90, or 100 fails because those guesses continue the false stacking pattern. Ignoring the first line fails because that line is the actual rule the level uses. Looking for a hidden arithmetic operation on the right-side numbers fails because the pattern is not meant to be extended at all. The intended reading is to take each equality as a direct pair, then read the pair for 5 from the pair already given for 1.

Tips & Common Mistakes

• Do not extend the 15, 215, 3215 sequence into the next stacked number. Those lines are decoys meant to push you toward the larger answer choices.
• Remember that equality works both ways. The first line says 1 = 5, so 5 = 1 as well, and that reverse value is the answer the board wants.
• Tap the small choice 1 in the answer row, not one of the large numbers. If you already picked a larger option and it was rejected, re-check the first equality before trying another choice.