







Soccer fans and cricket fans 
20180506 

From Chibo: In a survey of 60 sport fans, 45 enjoy soccer, 35 enjoy cricket and 10 do not enjoy either soccer or cricket, but some other sports.What percentage of sports fans enjoys both soccer and cricket? Answered by Penny Nom. 





How many students have neither brown hair or hazel eyes? 
20130120 

From Julie: There are 28 students in a class. 15 have brown hair, 17 have hazel eyes, and 10 have both. How many students have neither brown hair or hazel eyes? Answered by Penny Nom. 





Probability 
20120823 

From Christine: In a study of alcoholics, it was found out that 40% had alcoholic fathers and 6% had alcoholic mother. Fourtytwo percent had at least one alcoholic parent. What is the probability that a randomly selected alcoholic will ... Answered by Penny Nom. 





Conditional probability 
20100326 

From Sandy: In a certain school, it is known that 80% of the students use the internet for school projects, 60% use email on a regular basis, and 90% use the internet for school projects or for email on a regular basis. A student from this school is selected at random
Determine the probability that the student used email, given that the student used the internet for school projects.
Sandy Answered by Penny Nom. 





How many people in total came to the museum that day? 
20100305 

From simon: 1354 people attended exhibition A and 1427 people attended exhibition B. 79% of people attended both exhibitions. How many people in total came to the museum that day Answered by Penny Nom. 





An Euler diagram and a logic argument 
20080918 

From Regina: Use a Euler diagram to determine whether the following argument is valid or invalid.
No wizard can yodel
All lizards can yodel
No wizard is a lizard Answered by Penny Nom. 





All wiffs are miffs and all miffs are kiffs. 
20080608 

From Allison: All wiffs are miffs. all miffs are kiffs. There are 25 wiffs. There are 76 kiffs. 33 kiffs are not miffs. How many miffs are not wiffs? Answered by Penny Nom. 





A thanksgiving day problem 
20071117 

From svetik: On Thanksgiving Day, a group of nutty professors dressed up as "turkeys" and participated in a local fundraising event. The event consisted of three types of races: the sprint, the relay, and the hurdles. One more “turkey” takes part in the hurdles only than the sprint only. The same number take part in the sprint and the hurdles as take part in the relay and the hurdles. Eleven of the “turkeys” taking some part in these three races do not do the relay. Five “turkeys” take part in the sprint and the relay and three enter all three races. There are four teams of four “turkeys” in the relay. And, one more “turkey” is running in both the relay and the sprint than in the hurdles only.
“Turkey” Coe turned and said to “Turkey” Kim, “How many ‘turkeys’ were taking some part in any of the three races?” The nuttiest math professor, “Turkey” Young, said “There were ________ ‘turkeys’ taking part in any of the three races.”
Fill in the blank!!! Answered by Penny Nom. 





Brown hair and hazel eyes 
20050918 

From Julee: There are 28 students in a class. 15 have brown hair, 17 have hazel eyes, and 10 have both. How many students have neither brown hair or hazel eyes? Answered by Penny Nom. 





A problem with sets 
20040120 

From Jason:
Given that the universal set S is the set of all sports fans, and
F={xx is a football fan}
B={xx is a basketball fan}
H={xx is a hockey fan}
a)Describe (F^B)' (f intersect b)' in words
b)Draw a Venn Diagram and shade the region that represents the set of football fans or both basketball and hockey fans.
Answered by Penny Nom. 





I have three circles... 
20030130 

From Tony: I HAVE THREE CIRCLE THAT IS CIRCLE TOGETHER: IN CIRCLE A, THE NUMBERS ARE: 11 I KNOW IS IN CIRCLE A, BUT I HAVE THE: 5 THAT IN A AND C, I HAVE THE 2 IN THE CIRCLE C AND B AND AND A, THE CIRCLE C I KNOW THAT 10 IS IN THE CIRCLE THE 4 IN CIRCLE A: AND B: IN CIRCLE B, I KNOW NUMBER 13 IS IN CIRCLE B; BUT I HAVE THE 3 IN CIRCLE B AND C AND I HAVE THE 2 IN CIRCLE B AND C AND A ,THE 4 IN CIRCLE B AND A. HOW DO I FIND THE SUM IN CIRCLE C AND IN B IN BOTH CIRCLE A AND B AND B AND C NOT IN CIRCLE B, AND NOT CIRCLE C. Answered by Penny Nom. 





Baseball, basketball and football 
20021008 

From Debbie: The school newspaper is interviewing 6th grade students to see what sports they follow regularly on TV. Of the 70 students interviewed; 40 enjoyed basketball; 40 enjoyed baseball; 40 enjoyed football; 20 enjoyed basketball and football; 22 enjoyed baseball and basketball; 27 enjoyed football and baseball; and 12 enjoyed all three sports. How many students out of the 70 interviewed didn't follow any one of the three sports? Answered by Leeanne Boehm, Penny Nom and Walter Whiteley. 





Conditional probability 
20020519 

From Manny: In a certain school, it is known that 80% of the students use the internet for school projects, 60% use email on a regular basis, and 90% use the internet for school projects or for email on a regular basis. a student from this school is selected at random Determine thge probability that the student used email, given that the student used the internet for school projects. ANS: how can i solve this question by useing the vin diaagram Answered by Andrei Volodin. 





A health club 
20011125 

From Maria: A health club with a membership of 650 people operates a running track and an indoor swimming pool. A survey of the membership indicates that 68% use the running track, 44% use the swimming pool, and 8% use neither. If a member is chosen at random, what is the prbability that the member uses: a) Both the track and the pool? b) Only the track? Answered by Penny Nom. 





Derfs, Enajs and Sivads 
20010107 

From John and Norman: All Derfs are Enajs. Onethird of all Enajs are Derfs. Half of all Sivads are Enajs. One Sivad is a Derf. Eight Sivads are Enajs. The number of Enajs is 90. How many Enajs are neither Derf nor Sivad? Answered by Penny Nom. 





100% on two tests 
20000201 

From Craig and Chelsea Bruzzone: A class of 35 students took a math test and a science test. 12 students got 100% on the math test. 9 students got 100% on the science test. There were 19 students who made less than 100% on both tests. How many students made 100% on both tests? Answered by Penny Nom. 

