The World’s Shortest IQ Test

If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets?


A bat and a ball cost $1.10 in total. The bat costs $1.00 more than the ball. How much does the ball cost?


In a lake, there is a patch of lily pads. Every day, the patch doubles in size. If it takes 48 days for the patch to cover the entire lake, how long would it take for the patch to cover half of the lake?


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If you love quizzes and math puzzles, we have the perfect test for you to try your hand at. It is the shortest IQ test in the world, with only three questions, but fewer than one in five can take it correctly.

If you’ve ever wanted to test your intelligence but don’t have time to bother with taking a long IQ test, maybe we have the perfect solution for you. The world’s shortest IQ test consists of only three math questions and shouldn’t take too long. But be warned – it is quite difficult!

The Cognitive Reflection Test is not new. This is part of a research paper published in 2005 by MIT Professor Shane Frederick. This work recently appeared on the web, which made many people want to take on this test. As part of his research, Professor Frederick asked over 3,000 people to complete a test. participants from all walks of life, and even those who attended top US universities such as Yale and Harvard, had difficulty compiling all of the answers.

Of all the people who took part in the test, only 17 percent. all points were scored, which means that 83 percent. people failed the test.

According to Frederick, there are two general types of cognitive activity called “system 1” and “system 2” (these terms have been first used by Daniel Kahneman). System 1 is executed quickly without reflection, while system 2 requires conscious thought and effort. The cognitive reflection test has three questions and each has an obvious but incorrect response given by system 1. The correct response requires the activation of system 2. For system 2 to be activated, a person must note that their first answer is incorrect, which requires reflection on their own cognition.

The test has been found to correlate with many measures of economic thinking, such as numeracy, temporal discounting, risk preference, and gambling preference. It has also been correlated with measures of mental heuristics, such as the gambler’s fallacy, the understanding of regression to the mean, the sunk cost fallacy, and others.

Keith Stanovich found that cognitive ability is not strongly correlated with CRT scores because it will only lead to better CRT performance under certain conditions. First, the test-taker must recognize the need to override their system 1 response, and then they must have available cognitive resources to carry out the override. If the test-taker does not need to inhibit system 1 for the override, then the system 2 response immediately follows. Otherwise, they must have the capacity to sustain inhibition of system 1 to engage the system 2 response. Contrarily, some researchers have assessed the validity of the assessment, using an advanced item response theory method, and found that the CRT likely measures cognitive ability. The authors of the study explain the validity of the CRT has been questioned due to the lack of validity studies and the lack of a psychometric approach.

Studies have estimated that between 44 and 51% of research participants have previously been exposed to CRT. Those participants that are familiar with the CRT tend to outscore those with no previous exposure, which raises questions about the validity of the measure in this population. To combat limitations associated with familiarity, researchers have developed a variety of alternative measures of cognitive reflection. Recent research, however, suggests that the CRT is robust to multiple exposures so that despite the raw score increases in experienced participants, its correlations with other variables remain unaffected.

Another limitation is due to a lack of strong psychometric properties and a scarcity of validity studies in the literature. The CRT was not designed in a manner that aligns with standards of the industry such as the Standards for Educational and Psychological Testing which was developed by the American Educational Research Association, American Psychological Association, & National Council on Measurement in Education.

In psychology, a dual process theory provides an account of how thought can arise in two different ways, or as a result of two different processes. Often, the two processes consist of an implicit (automatic), unconscious process and an explicit (controlled), conscious process. Verbalized explicit processes or attitudes and actions may change with persuasion or education; though implicit processes or attitudes usually take a long amount of time to change with the forming of new habits. Dual process theories can be found in social, personality, cognitive, and clinical psychology. It has also been linked with economics via prospect theory and behavioral economics, and increasingly in sociology through cultural analysis.

The foundations of dual process theory likely come from William James. He believed that there were two different kinds of thinking: associative and true reasoning. James theorized that empirical thought was used for things like art and design work. For James, images and thoughts would come to mind from past experiences, providing ideas of comparison or abstractions. He claimed that associative knowledge was only from past experiences describing it as “only reproductive”. James believed that true reasoning could enable overcoming “unprecedented situations” just as a map could enable navigating past obstacles.

Various dual-process theories were produced after William James’s work. Dual process models are very common in the study of social psychological variables, such as attitude change. Examples include Petty and Cacioppo’s elaboration likelihood model and Chaiken’s heuristic systematic model. According to these models, persuasion may occur after either intense scrutiny or extremely superficial thinking. In cognitive psychology, attention and working memory have also been conceptualized as relying on two distinct processes. Whether the focus is on social psychology or cognitive psychology, there are many examples of dual-process theories produced throughout the past. The following just show a glimpse into the variety that can be found.

Peter Wason and Jonathan Evans suggested the dual process theory in 1974. In Evans’ later theory, there are two distinct types of processes: heuristic processes and analytic processes. He suggested that during heuristic processes, an individual chooses which information is relevant to the current situation. Relevant information is then processed further whereas irrelevant information is not. Following the heuristic, processes come analytic processes. During analytic processes, the relevant information that is chosen during the heuristic processes is then used to make judgments about the situation.

Richard E. Petty and John Cacioppo proposed a dual process theory focused on the field of social psychology in 1986. Their theory is called the elaboration likelihood model of persuasion. In their theory, there are two different routes to persuasion in making decisions. The first route is known as the central route and this takes place when a person is thinking carefully about a situation, elaborating on the information they are given, and creating an argument. This route occurs when an individual’s motivation and ability are high. The second route is known as the peripheral route and this takes place when a person is not thinking carefully about a situation and uses shortcuts to make judgments. This route occurs when an individual’s motivation or ability is low.

Steven Sloman produced another interpretation of dual processing in 1996. He believed that associative reasoning takes stimuli and divides them into logical clusters of information based on statistical regularity. He proposed that how you associate is directly proportional to the similarity of past experiences, relying on temporal and similarity relations to determine reasoning rather than an underlying mechanical structure. The other reasoning process in Sloman’s opinion was the Rule-based system. The system functioned on logical structure and variables based upon rule systems to come to conclusions different from that of the associative system. He also believed that the Rule-based system had control over the associative system, though it could only suppress it. This interpretation corresponds well to earlier work on computational models of dual processes of reasoning.

Daniel Kahneman provided further interpretation by differentiating the two styles of processing more, calling them intuition and reasoning in 2003. Intuition (or system 1), similar to associative reasoning, was determined to be fast and automatic, usually with strong emotional bonds included in the reasoning process. Kahneman said that this kind of reasoning was based on formed habits and was very difficult to change or manipulate. Reasoning (or system 2) was slower and much more volatile, being subject to conscious judgments and attitudes.

Fritz Strack and Roland Deutsch proposed another dual process theory focused on the field of social psychology in 2004. According to their model, there are two separate systems: the reflective system and the impulsive system. In the reflective system, decisions are made using knowledge and the information that is coming in from the situation is processed. On the other hand, in the impulsive system, decisions are made using schemes and there is little or no thought required.

Ron Sun proposed a dual-process model of learning (both implicit learning and explicit learning). The model (named CLARION) re-interpreted voluminous behavioral data in psychological studies of implicit learning and skill acquisition in general. The resulting theory is two-level and interactive, based on the idea of the interaction of one-shot explicit rule learning (i.e., explicit learning) and gradual implicit tuning through reinforcement (i.e. implicit learning), and it accounts for many previously unexplained cognitive data and phenomena based on the interaction of implicit and explicit learning.

The Dual Process Learning model can be applied to a group-learning environment. This is called The Dual Objective Model of Cooperative Learning and it requires a group practice that consists of both cognitive and affective skills among the team. It involves active participation by the teacher to monitor the group throughout its entirety until the product has been successfully completed. The teacher focuses on the effectiveness of cognitive and affective practices within the group’s cooperative learning environment. The instructor acts as an aide to the group by encouraging their positive affective behavior and ideas. In addition, the teacher remains, continually watching for improvement in the group’s development of the product and interactions amongst the students. The teacher will interject to give feedback on ways the students can better contribute affectively or cognitively to the group as a whole. The goal is to foster a sense of community amongst the group while creating a proficient product that is a culmination of each student’s unique ideas.

We present to you the shortest IQ test in the world! Can you answer correctly the three questions in our quiz? Click the start button and see for yourself now!