You have two hourglasses, a 7 minute one and an 11 minute one. Using just these two hourglasses, how can you accurately time 15 minutes?
Riddle AnswerMath Riddles
1.5 Teenagers 1.5 Pizzas 1.5 Days
If one and a half teenagers can eat one and a half pizzas in one and a half days, how many pizzas can 9 teenagers eat in 3 days?
Riddle AnswerTwelve Flags
Twelve flags stand equidistant along the track at the stadium. The runners start at the first flag. A runner reaches the eighth flag 8 seconds after he starts. If he runs at an even speed, how many seconds does he need altogether to reach the twelfth flag?
Riddle AnswerSchoolboy’s Route
Each morning Boris walks to school. At one-fourth of the way he passes the machine and tractor station; at one-third of the way, the railroad station. At the machine and tractor station its clock shows 7:30, and at the railroad station its clock shows 7:35.
When does Boris leave his house, when does he reach school?
Riddle AnswerHalf as Many Sisters as Brothers
A boy has as many sisters as brothers, but each sister has only half as many sisters as brothers. How many brothers and sisters are there in the family?
Riddle Answer