Percentage & Data Handling Quiz

Explanation
To find 30% of 150 kg, we multiply 150 kg by 0.30 (which is the decimal equivalent of 30%). This calculation gives us 45 kg. Therefore, the correct answer is 45 kg.

Explanation
To find the answer, we need to increase $150 by 20%. To calculate the increase, we multiply $150 by 20% (or 0.20). 20% of $150 is $30. Adding this to the original amount, we get $180. Therefore, the correct answer is $180.

Explanation
The percentage decrease can be calculated by finding the difference between the initial value and the final value, dividing it by the initial value, and then multiplying by 100. In this case, the initial value is 80 kg and the final value is 72 kg. The difference is 80 kg - 72 kg = 8 kg. Dividing 8 kg by 80 kg gives 0.1, and multiplying by 100 gives 10%. Therefore, the percentage decrease is 10%.

Explanation
After applying a discount of 25% to the original price of 100 QR, the discounted price can be calculated by multiplying the original price by (100% - 25%) = 75%. Therefore, the price after the discount is 75 QR.

Explanation
The sample consisting of 25 people is considered a small sample because it has the smallest number of people compared to the other samples provided (35 and 30 people). In statistical terms, a small sample size refers to a subset of a population that is not representative enough to draw accurate conclusions or make generalizations about the entire population.

Explanation
The question asks for the number of cars sold in one week by a large store. The chart provided does not directly indicate the number of cars sold, but instead shows the color of cars sold. Therefore, there is no clear way to determine the exact number of cars sold based on the given information. Hence, the correct answer cannot be determined.

Explanation
The correct answer is "Number of your brother" and "Number of students in your class". These two options represent quantitative discrete data because they involve counting and measuring distinct, separate entities. The number of brothers a person has and the number of students in a class are both numerical values that can only take on specific whole numbers, making them examples of discrete data. On the other hand, "Your favorite color" is not a quantitative data type as it is a subjective preference and cannot be measured or counted in the same way.

Explanation
The answer is 18 because there are three numbers given in the table, and all three numbers are 10 or more. Therefore, the number of students who take 10 or more marks is 18.

Explanation
The histogram shows the number of minutes teens spend on the internet answering email messages. The bars represent different time intervals, and the heights of the bars represent the number of teens who spend that amount of time. The question asks how many teens spend between 21-40 minutes. Looking at the histogram, we can see that there are 11 teens represented in the bar for that time interval.

Explanation
The pie chart represents the 2007 road toll, showing the distribution of fatalities among different road user types. The question asks for the road user type that accounted for the least fatalities in 2007. Looking at the chart, we can see that the segment representing cyclists is the smallest, indicating that they accounted for the least number of fatalities compared to passengers and drivers. Therefore, the correct answer is cyclist.

Explanation
Based on the pie chart, the percentage of immigrants from China is 9%. To find the number of immigrants from China, we can use the formula: (9/100) x 30000 = 2700. Therefore, 2700 immigrants arrived from China.

Explanation
The pie chart represents the preferences of 60 pupils for their favorite color. The question asks how many people chose red. Since the answer is given as 15, it can be inferred that 15 out of the 60 pupils, or one-fourth of them, chose red as their favorite color.