Statistics

The following bar graph shows the number of students who joined different hobby clubs in a school. Based on the graph, what is the difference between the number of students in the Music club and the number of students in the Craft club?

If the lower limit of a class is $20$ and the class size is $10$, what is the upper limit?

In a bar graph, if $1$ unit length represents $5$ cars, then $7$ units length represents:

The data collected by an investigator herself with a definite objective in her mind is called:

A grouped frequency distribution has class intervals $0-10, 10-20, 20-30$. Which interval does the value $20$ belong to in the exclusive method?

What is the mean of the first five prime numbers?

In a histogram, if a class interval $10-20$ has a frequency of $5$ and the next interval $20-30$ has a frequency of $10$, what is the change in the height of the bars?

A data set has a median of 25. If every value in the data set is increased by 5 and then multiplied by 2, what will be the new median?

In a study of 500 components, a failure rate graph is plotted as a frequency polygon. If the sum of the frequencies is represented by the total area under the polygon when class width is 1, and the current class width is 10, what factor must the heights be multiplied by to keep the area equal to the total frequency?

A histogram is drawn for the distribution of ages of residents. For the class $25-30$, the frequency is 40. For the class $30-40$, the frequency is 60. What is the ratio of the areas of the rectangles representing these two classes?

Which of the following is the most frequent value in a data set?

The mean of 10, 20, 30, 40 is:

What is the median of $1, 2, 3, 4, 5, 6, 7, 8, 9, 10$?

If the mean of five observations is 15, and the sum of the first four is 60, what is the fifth observation?

If the mean of the observations $x, x+3, x+5, x+7, x+10$ is 9, then what is the mean of the last three observations?

In a symmetric distribution (where data is perfectly balanced), which of the following is usually true?

The average of three numbers is 10. If the average of the first two numbers is 9, what is the third number?

If $x_1, x_2, \dots, x_{10}$ are $10$ observations such that $\sum_{i=1}^{10} x_i = 150$, and a new observation $x_{11} = 40$ is added, find the new mean.

Calculate the mean of the squares of the first $3$ natural numbers.

The mean of $100$ observations is $50$. If one of the observations, which was $50$, is replaced by $150$, what is the new mean?

If the mean height of $10$ boys is $150$ cm and the mean height of $30$ girls is $140$ cm, what is the mean height of the group?

A mixture has $3$ parts of substance A (mean value $10$) and $1$ part of substance B (mean value $30$). What is the average value of the mixture?

A student scores $80\%$ in a $100$-mark paper and $90\%$ in a $200$-mark paper. What is the overall percentage score?

A farmer has $40$ sheep with mean weight $50$ kg and $10$ cows with mean weight $300$ kg. What is the mean weight of all $50$ animals?

A gold smith mixes $10$ g of $22$-carat gold with $20$ g of $18$-carat gold. What is the purity of the resulting gold in carats?

In a library, $60\%$ of the books are in English with an average of $300$ pages, and $40\%$ are in Hindi with an average of $250$ pages. What is the average number of pages per book?

A worker is paid $₹100$ per hour for the first $40$ hours and $₹150$ per hour for $10$ hours of overtime. What is his average hourly wage?

The weighted mean of $n_1$ and $n_2$ items with means $x_1$ and $x_2$ is $X$. If $n_1/n_2 = k$, express $X$ in terms of $x_1, x_2,$ and $k$.

The mean of $5$ observations is $4.4$ and their variance is $8.24$. If three of the observations are $1, 2,$ and $6$, find the other two observations assuming they are integers.

A company reports an average growth of $10\%$ in its first $3$ years and $15\%$ in the next $2$ years. What is the weighted average annual growth rate over the $5$-year period?

Based on a 100% stacked bar graph for a class of 40 students, 60% are girls. How many boys are in the class?

In a survey of 400 people, a 100% stacked bar graph shows that 25% of people prefer Coffee. How many people do NOT prefer Coffee?

A stacked bar graph shows the population of two towns. Town A: 3000 males, 2000 females. Town B: 2500 males, 3000 females. What is the total population of Town B?

A school collects plastic and paper for recycling. In January, they collected 20kg plastic and 30kg paper. In February, they collected 25kg plastic and 25kg paper. Which month had a higher total mass of recycled material?

A school conducted a survey to find the preferred extra-curricular activities among Class 9 students in two different sections, A and B. The results are represented in the 100% stacked bar graph below. If Section A has 40 students and Section B has 50 students, find the difference between the number of students who prefer 'Sports' in Section B and Section A.

In the stacked bar chart for monthly rainfall, the lower part is 'Rain' and the upper part is 'Snow'. If in December, 'Rain' was 10cm and 'Snow' was 15cm, and in January 'Rain' was 5cm and 'Snow' was 25cm, which month had more total precipitation?

Two years of production (Wheat and Rice) are shown. Year 1: Wheat = 50, Rice = 40. Year 2: Wheat = 60, Rice = 30. Which statement is true?

A $100\%$ stacked bar graph compares the demographics of two clubs. Club Alpha has $70\%$ male members. Club Beta has a $1:1$ male-to-female ratio. If the two clubs merge and Club Alpha has 200 members while Club Beta has 300 members, what is the percentage of males in the merged 'Total' stack?

A stacked bar graph shows the weight of two metals in an object. In Object 1 (Total 10kg), Metal A is 4kg. Object 2 is made by melting Object 1 and adding 2kg of Metal B. What is the percentage of Metal A in the stacked bar for Object 2?

Given a $100\%$ stacked bar graph of a farmer's crop yield (Wheat and Rice). In Year 1, Wheat was $60\%$. In Year 2, the actual yield of Wheat stayed the same as Year 1, but the actual yield of Rice doubled. What is the new percentage of Wheat in the Year 2 bar?