Question

Madam Curie collects equal quantities (each 1 gram) of radio active elements, radium, and polonium in two containers. She uses 1/2 part of radium and 1/3 part of polonium in an experiment. What quantity of radium and polonium is left out (in grams) is represented on the given number line?

• A. Radium : $\frac{1}{2}$ grams, Polonium: $\frac{2}{3}$ grams.
• B. Radium: $\frac{2}{3}$ grams, Polonium: $\frac{1}{3}$ grams.
• C. Radium : $\frac{3}{2}$ grams, Polonium: $\frac{2}{3}$ grams.
• D. Radium : $\frac{5}{2}$ grams, Polonium: $\frac{3}{2}$ grams.

Answer 1

The correct option is A Radium : $\frac{1}{2}$ grams, Polonium: $\frac{2}{3}$ grams.

Given: 1 gram of radium and polonium are stored in separate containers.

$\frac{1}{2}$ of radium is used.

In the given number line , each segment is divided into two parts.
Each part represents $\frac{1}{2}$

Hence, remaining radium = $\frac{1}{2}$ grams

$\frac{1}{3}$ gram of polonium is used.

To find the remaining polonium, check the marked point on the number line.

Each segment is divided into 3 parts. Each part represents $\frac{1}{3}$

Point is marked at the 2nd place from zero.

Hence, 2 $\times$ $\frac{1}{3}$ = $\frac{2}{3}$ grams of polonium is left in the container.

= $\frac{2}{3}$

Hence, remaining quantity of radium = $\frac{1}{2}$ grams and remaining quantity of polonium = $\frac{2}{3}$ grams.