Class 8 Practice – Level 3 – Set 1 – Data Handling

Total questions: 15

A survey of $50$ students revealed that the average marks scored in Math is $72$ with a standard deviation of $8$. If the marks are normally distributed, approximately how many students scored between $64$ and $80$?

Topic: Probability

$34$

$38$

$40$

$42$

None

A frequency distribution of marks is as follows:

Topic: Organizing Data

Marks	Frequency
10-20	5
20-30	8
30-40	15
40-50	10
50-60	7

What is the cumulative frequency for the class $40-50$?

$20$

$28$

$38$

$45$

None

In a school, $60$ students appeared for a Math test. The mean of the top $10$ students is $85$, and the mean of the remaining $50$ students is $65$. What is the mean of all $60$ students?

Topic: Measures of Central Tendency

$67.5$

$70$

$72.5$

$75$

None

A coin is tossed $5$ times. What is the probability of getting at least $3$ heads?

Topic: Probability

$\dfrac{1}{16}$

$\dfrac{5}{16}$

$\dfrac{13}{32}$

$\dfrac{19}{32}$

None

A die is rolled $3$ times. What is the probability of getting at least one $6$?

Topic: Probability

$\dfrac{1}{6}$

$\dfrac{91}{216}$

$\dfrac{125}{216}$

$\dfrac{91}{125}$

None

A card is drawn randomly from a standard deck of $52$ cards. What is the probability of getting a face card or a spade?

Topic: Probability

$\dfrac{19}{52}$

$\dfrac{23}{52}$

$\dfrac{11}{26}$

$\dfrac{25}{52}$

None

The mean of $20$ observations is $25$. If two values $15$ and $35$ are removed, what will be the new mean?

Topic: Measures of Central Tendency

$24$

$25$

$26$

$28$

None

The median of the data $15, 18, 21, 25, 30, 35, 40, 45, 50, 55$ is:

Topic: Measures of Central Tendency

$30$

$32.5$

$35$

$37.5$

None

The range of the data set $12, 20, 32, 40, 18, 24, 28$ is:

Topic: Organizing Data

$18$

$28$

$30$

$40$

None

10.

A histogram represents the marks obtained by $50$ students in a Math test. The class intervals are $10-20$, $20-30$, $30-40$, $40-50$. The height of the bar for $30-40$ is $15$. What is the frequency for this class interval?

Topic: Graphical Representation of Data

$5$

$10$

$15$

Cannot be determined

None

11.

A box contains $10$ white, $5$ black, and $8$ red balls. What is the probability of drawing either a black or a red ball?

Topic: Probability

$\dfrac{8}{23}$

$\dfrac{13}{23}$

$\dfrac{15}{23}$

$\dfrac{18}{23}$

None

12.

The mode of the data $5, 8, 8, 9, 12, 15, 8, 7$ is:

Topic: Measures of Central Tendency

$8$

$9$

$12$

None of the above

None

13.

A dice is rolled $4$ times. What is the probability of getting the number $3$ at least twice?

Topic: Probability

$\dfrac{1}{6}$

$\dfrac{25}{216}$

$\dfrac{125}{324}$

$\dfrac{91}{216}$

None

14.

The following data represents the monthly salaries (in thousands) of $10$ employees: $15, 18, 20, 22, 25, 28, 30, 30, 35, 50$. Find the median salary.

Topic: Measures of Central Tendency

$24.5$

$25$

$27.5$

$30$

None

15.

The variance of the data $6, 8, 10, 12, 14$ is:

Topic: Measures of Central Tendency

$4$

$8$

$10$

$12$

None

1 out of 15

Time's up

Class 8 Practice – Level 3 – Set 1 – Data Handling

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