Question

The following pie charts show the distribution of students studying Science and Commerce in three different schools namely A, B, C.
The ratio of the number of students studying Science to that studying Commerce in school B is:

• A. $3:4$
• B. $2:3$
• C. $1:2$
• D. $1:1$

Answer 1

The correct option is C $1:2$

Step 1: Given, total number of students in Science $=400$

Central angle of the school B sector $={90}^{\circ }$
$\therefore \text{Number of students studying Science in school}B$
$\text{= Total number of students in Science}\times \text{Fraction of school}B$
$=400\times \frac{{90}^{\circ }}{{360}^{\circ }}$
$=400\times \frac{1}{4}$
$=100$

Step 2: Total number of students in Commerce $=600$

Central angle of the school B sector $={120}^{\circ }$
$\therefore \text{Number of students studying Commerce in school}B$
$\text{= Total number of students in Commerce}\times \text{Fraction of school}B$
$=600\times \frac{{120}^{\circ }}{{360}^{\circ }}$
$=600\times \frac{1}{3}$
$=200$

Step 3: $\text{Ratio of the number of students studying Science to that studying Commerce in school B}$
$=\text{Number of students studying Science in school}B\text{: Number of students studying Commerce in school}B$
$=100:200$
Divide both sides by 100
$=\frac{100}{100}:\frac{200}{100}$
$=1:2$

Option(c.) is the correct choice.