Question

the graph shows the relationship between the number of correct answers given by mini and the number of marks she scored. how many marks did she score for 11 correct answers? a 5 b 18 c 20 d 22

Explanation:

Step1: Identify data - points

We need to find the marks corresponding to 11 correct answers from the graph - data. Since the graph is not provided completely, we assume a linear - like relationship and use the given data points (5, 18), (20, 22) to find a possible relationship. First, find the slope of the line passing through two points $(x_1,y_1)=(5,18)$ and $(x_2,y_2)=(20,22)$. The slope $m=\frac{y_2 - y_1}{x_2 - x_1}=\frac{22 - 18}{20 - 5}=\frac{4}{15}$.

Step2: Use point - slope form

The point - slope form of a line is $y - y_1=m(x - x_1)$. Using the point $(x_1,y_1)=(5,18)$ and $m = \frac{4}{15}$, we have $y-18=\frac{4}{15}(x - 5)$.
Substitute $x = 11$ into the equation:
\[

$$\begin{align*} y-18&=\frac{4}{15}(11 - 5)\\ y-18&=\frac{4}{15}\times6\\ y-18&=\frac{24}{15}=\frac{8}{5}=1.6\\ y&=18 + 1.6\\ y&=19.6 \end{align*}$$

\]

Answer:

19.6 (assuming a linear relationship based on the given data points)