How many more students preferred apples than oranges?

$$
V = (12 \text{ m})^3
$$

$$
V = 12 \text{ m} \times 12 \text{ m} \times 12 \text{ m}
$$
$$
V = 1,728 \text{ m}^3
$$
Ujazo wa mchemraba ni: $\boxed{1,728 \text{ m}^3}$

$$
54 \times 3 = 162
$$
Nambari inayokosekana ni: $\boxed{162}$

$$
\text{Vipande vilivyobaki} = \text{Jumla ya vipande} - \text{Vipande vilivyoliwa}
$$
$$
\text{Vipande vilivyobaki} = 8 - 3 = 5
$$

$$
\text{Sehemu iliyobaki} = \frac{\text{Vipande vilivyobaki}}{\text{Jumla ya vipande}}
$$
$$
\text{Sehemu iliyobaki} = \frac{5}{8}
$$
Sehemu ya pizza iliyobaki ni: $\boxed{\frac{5}{8}}$

$$
15\% = \frac{15}{100}
$$

$$
\frac{15}{100} \times 200
$$
$$
15 \times 2 = 30
$$
Thamani ni: $\boxed{30}$

$$
\text{Jumla} = 10 + 20 + 30 + 40 + 50 = 150
$$

$$
\text{Wastani} = \frac{\text{Jumla}}{\text{Idadi ya nambari}} = \frac{150}{5}
$$
$$
\text{Wastani} = 30
$$
Wastani wa nambari hizo ni: $\boxed{30}$

$$
2y - 4 + 4 = 10 + 4
$$
$$
2y = 14
$$

$$
\frac{2y}{2} = \frac{14}{2}
$$
$$
y = 7
$$
Thamani ya $y$ ni: $\boxed{7}$

*   Wanafunzi waliochagua tufaha (Apples): 8
*   Wanafunzi waliochagua machungwa (Oranges): 6

$$
\text{Tofauti} = \text{Wanafunzi waliochagua tufaha} - \text{Wanafunzi waliochagua machungwa}
$$
$$
\text{Tofauti} = 8 - 6 = 2
$$
Wanafunzi 2 zaidi walipendelea tufaha kuliko machungwa. $\boxed{2}$