Answer:
(a) 8/15
(b) 192°
Explanation:
The total number of students in the class is the sum of the frequencies:
![\begin{aligned}\implies \textsf{Total number of students} &= \sf4 + 8 + 3\\& =\sf 15\end{aligned}](https://img.qammunity.org/2023/formulas/mathematics/high-school/qhga11s6cuo866xkpglk0e284rmva7ynb0.png)
Part (a)
To find the fraction of the students who said science was their favorite subject, divide the frequency of science by the total number of students:
![\implies \sf Science = (8)/(15)](https://img.qammunity.org/2023/formulas/mathematics/high-school/5avuvb9gf1pwjm8i3frairn15gk4ekozg4.png)
Part (b)
A pie chart is a type of graph in which a circle is divided into sections that each represent a proportion of the whole.
A circle has a total of 360° all the way around its center.
Therefore, the central angle of the section of a pie chart that represents science is ⁸/₁₅ths of 360°:
![\begin{aligned}\implies \sf Central\:Angle\:(Science) & = \sf (8)/(15) \; of \; 360^(\circ)\\\\& = \sf (8)/(15) * 360^(\circ)\\\\& = \sf (8* 360^(\circ))/(15) \\\\& = \sf (2880^(\circ))/(15) \\\\& =\sf 192^(\circ) \end{aligned}](https://img.qammunity.org/2023/formulas/mathematics/high-school/ro8xsi4dhvw9mbtrspohqwfggdqahtljie.png)