Question 1
A study was designed to investigate the effects of two variables — (1) a student's level of mathematical anxiety and (2) teaching method — on a student's achievement in a mathematics course. Students who had a low level of mathematical anxiety were taught using the traditional expository method. These students obtained a mean score of 470 with a standard deviation of 50 on a standardized test. Assuming a non-mound-shaped distribution, what percentage of the students scored over 620?
◦ at most 11%
◦ at least 89%
◦ at most 5.5%
◦ approximately 2.5%
Question 2
A recent survey was conducted to compare the cost of solar energy to the cost of gas or electric energy. Results of the survey revealed that the distribution of the amount of the monthly utility bill of a 3-bedroom house using gas or electric energy had a mean of $104 and a standard deviation of $10. If nothing is known about the shape of the distribution, what percentage of homes will have a monthly utility bill of less than $84?
◦ at least 88.9%
◦ at most 25%
◦ at most 11.1%
◦ at least 75%
Models for the electron orbitals and energy shells of carbon
Carbon dioxide emission per gigajoule of energy released
Electric Charges
Variations in Solar Angle with Latitude
Contributions to the free energy of folding of globular proteins
The Visible Spectrum of Electromagnetic Energy