Solution

Let \( x \) be the number of slices for 3 children. \[ \begin{array}{|c|c|} \hline \text{No. of children} & 2 & 3 \\ \hline \text{No. of slices} & 3 & x \\ \hline \end{array} \]

As the number of children increase, the number of pizza slices will decrease. It is a case of inverse variation

\[ \begin{align*} \implies a \times b &= k \text{ (constant)} \\ \\ 2 \times 3 &= 3 \times x \\ \\ x &= \frac{2 \times \cancel3^1}{\cancel3_1} \\ \\ \color{green} x &= \color{green} 2 \end{align*} \]

Answer Each children will get \( \color{red} 2 \text{ slices of pizza} \)

Answer No, Junk food causes obesity, diseases etc

Solution

Let \( x \) be the distance covered in 20 minutes. \[ \begin{array}{|c|c|c|} \hline \text{Time (minutes)} & 30 & 20 \\ \hline \text{Distance (km)} & 2 & x \\ \hline \end{array} \]

As the time decreases, the distance covered will also decrease. It is a case of direct variation.

\[ \begin{align*} \frac{x}{y} &= k \text{ (constant)} \\ \\ \frac{30}{2} &= \frac{20}{x} \\ \\ 30 \times x &= 20 \times 2 \\ \\ x &= \frac{\cancel{20}^2 \times 2}{\cancel{30}_3} \\ \\ x &= \frac{4}{3} \\ \\ \color{green} x &= \color{green} 1.33 \end{align*} \]

Answer Distance covered in 20 minutes \( = \color{red} 1.33 \text{ km} \)

Answer Keeps the body healthy.