B3. In the final of the Just Dance dance competition, an evaluation system was used to determine the winning pair. First, the expert committee awarded points and recorded them in a table:

| Dance Pair No. | 4 | 27 | 15 | 8 | 11 |
| :--- | ---: | ---: | ---: | ---: | ---: |
| Footwork Technique (T) | 3 | 2 | 3 | 1 | 3 |
| Choreography (K) | 1 | 2 | 1 | 3 | 2 |
| Dance Figure (F) | 2 | 2 | 3 | 3 | 3 |
| Dance Expression (I) | 3 | 2 | 2 | 3 | 2 |

where 3 points mean excellent, 2 points good, and 1 point satisfactory.

To calculate the final score (FS), the following formula was used:

$$
\mathrm{FS}=3 T+K+2 F+I
$$

A Calculate the final score for the pair No. 15.

B In which category were the dance pairs rated the lowest on average?

C Which pair won?

D Pair No. 4 believes that the formula for calculating the final score is unfair. Write a formula for calculating the final score that would allow this pair to win. The formula must be of the form

$$
\mathrm{FS}=\square T+\square K+\square F+\square I
$$

where you must fill in each blank with a natural number less than or equal to 3.
B3. Pair No. 15 scored 3 * 3 points for foot technique, 1 * 1 point for choreography, 2 * 3 points for dance figure, and 1 * 2 points for dance expression. In total, 18 points.

B Average scores of pairs from:

- foot technique $\frac{12}{5}$
- choreography $\frac{9}{5}$
- dance figure $\frac{13}{5}$
- dance expression $\frac{12}{5}$

On average, pairs were rated the lowest in choreography.

C Scoring of pairs:

| Pair | T | K | F | I | $\sum$ |
| :---: | :---: | :---: | :---: | :---: | :---: |
| 4 | 9 | 1 | 4 | 3 | 17 |
| 27 | 6 | 2 | 4 | 2 | 14 |
| 15 | 9 | 1 | 6 | 2 | 18 |
| 8 | 3 | 3 | 6 | 3 | 15 |
| 11 | 9 | 2 | 6 | 2 | 19 |

D Pair No. 4 will win according to the formula: $2 T+1 K+1 F+3 I$ or $3 T+1 K+1 F+3 I$.

Scoring: Total: 7 points

A Pair No. 15 scored 18 points. ..................................................... 1 p

B On average, pairs were rated the lowest in choreography. ........................... 2 p

C Answer, e.g.: Pair No. 11 won. ..................................................... 2 p

D One of the formulas according to which Pair No. 4 will win: $2 T+1 K+1 F+3 I$ or $3 T+$ $\qquad$