Question

The dot plot represents a random sample of 15 students studying science and economics as shown.

The measure of centre of science is and economics is .

• A. 9 hours
• B. 6 hours
• C. 8 hours
• D. 7 hours

Answer 1

Answer: (C), (D)

7 hours

From the given data, the shape of the both distributions are symmetric.
Hence, Mean is the measure of centre for both distributions.

Mean for Science:
= $\frac{6+6+7+7+7+8+8+8+9+9+9+10+10}{13}$

= $\frac{104}{13}$

= 8 hours

Mean for Economics:
= $\frac{4+5+5+6+6+7+7+7+8+8+9+9+10}{13}$

= $\frac{91}{13}$

= 7 hours

$\therefore$The measure of centre for studying science is 8 hours and economics is 7 hours.