Answer to June 2003 Newsletter Brain Teaser:

Find a common denominator of 2, 4 and 7 that is less than 30 - that number is 28. Then add up the calculated numbers of students. Two students received a B, 1/4 of 28, or 7 failed, 1/2 of 28, or 14, received a D, 1/7 of 28, or 4, received a C; which means only one student received an A.